<?xml version="1.0" encoding="UTF-8"?>

<!--XBRL Document Created with Wdesk from Workiva-->
<!--Copyright 2020 Workiva-->
<!--r:0108aff0-0485-4154-a0d7-7bdfc58c62aa,g:7e1880b9-c607-4ccf-a41d-ac6a6b8617b2-->
<link:linkbase xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/all" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#all"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#hypercube-dimension"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-default"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#dimension-domain"/>
  <link:arcroleRef arcroleURI="http://xbrl.org/int/dim/arcrole/domain-member" xlink:type="simple" xlink:href="http://www.xbrl.org/2005/xbrldt-2005.xsd#domain-member"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/DocumentandEntityInformation" xlink:type="simple" xlink:href="mtrx-20200630.xsd#DocumentandEntityInformation"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/DocumentandEntityInformation" xlink:type="extended" id="ib33d0d8467504b66b83745454e3d0b95_DocumentandEntityInformation"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/ConsolidatedStatementsofIncome" xlink:type="simple" xlink:href="mtrx-20200630.xsd#ConsolidatedStatementsofIncome"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/ConsolidatedStatementsofIncome" xlink:type="extended" id="i2d0bc76f7741432ead1c3ea56fdd3537_ConsolidatedStatementsofIncome"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/ConsolidatedStatementsofComprehensiveIncome" xlink:type="simple" xlink:href="mtrx-20200630.xsd#ConsolidatedStatementsofComprehensiveIncome"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/ConsolidatedStatementsofComprehensiveIncome" xlink:type="extended" id="i40d2173f8648436a85dd0bda3588c553_ConsolidatedStatementsofComprehensiveIncome"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/ConsolidatedStatementsofComprehensiveIncomeParentheticals" xlink:type="simple" xlink:href="mtrx-20200630.xsd#ConsolidatedStatementsofComprehensiveIncomeParentheticals"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/ConsolidatedStatementsofComprehensiveIncomeParentheticals" xlink:type="extended" id="ib5f72f14ee9c44a3baad32d634673161_ConsolidatedStatementsofComprehensiveIncomeParentheticals"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/ConsolidatedBalanceSheets" xlink:type="simple" xlink:href="mtrx-20200630.xsd#ConsolidatedBalanceSheets"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/ConsolidatedBalanceSheets" xlink:type="extended" id="i231e545894384104b51f5925d419b047_ConsolidatedBalanceSheets"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/ConsolidatedBalanceSheetsParenthetical" xlink:type="simple" xlink:href="mtrx-20200630.xsd#ConsolidatedBalanceSheetsParenthetical"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/ConsolidatedBalanceSheetsParenthetical" xlink:type="extended" id="ie2c210be889143449aea122ea224d530_ConsolidatedBalanceSheetsParenthetical"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/ConsolidatedStatementsofCashFlows" xlink:type="simple" xlink:href="mtrx-20200630.xsd#ConsolidatedStatementsofCashFlows"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/ConsolidatedStatementsofCashFlows" xlink:type="extended" id="i2e02b8caa2894136803bba1ffd8a7660_ConsolidatedStatementsofCashFlows"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/ConsolidatedStatementsofChangesinStockholdersEquity" xlink:type="simple" xlink:href="mtrx-20200630.xsd#ConsolidatedStatementsofChangesinStockholdersEquity"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/ConsolidatedStatementsofChangesinStockholdersEquity" xlink:type="extended" id="i7da825fff31f43329807184174f6336a_ConsolidatedStatementsofChangesinStockholdersEquity">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_45d801a7-f5fe-4313-9d31-0a40db8d1174" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_f8ce75c8-c4a3-402c-b835-e99e0a435d69" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_IncreaseDecreaseInStockholdersEquityRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_45d801a7-f5fe-4313-9d31-0a40db8d1174" xlink:to="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_f8ce75c8-c4a3-402c-b835-e99e0a435d69" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_58dc9d4c-dd18-45a6-8a49-b9b2b32519d1" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_f8ce75c8-c4a3-402c-b835-e99e0a435d69" xlink:to="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_58dc9d4c-dd18-45a6-8a49-b9b2b32519d1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProfitLoss_68a03d9e-2b07-493f-bc57-f8f77ffbcf62" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ProfitLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_f8ce75c8-c4a3-402c-b835-e99e0a435d69" xlink:to="loc_us-gaap_ProfitLoss_68a03d9e-2b07-493f-bc57-f8f77ffbcf62" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_a1139436-01e8-47f1-b09e-0261a6df331e" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_f8ce75c8-c4a3-402c-b835-e99e0a435d69" xlink:to="loc_us-gaap_OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent_a1139436-01e8-47f1-b09e-0261a6df331e" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan_e5058a08-9568-40d1-b37b-9a6bbab2e2e2" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_f8ce75c8-c4a3-402c-b835-e99e0a435d69" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueEmployeeStockPurchasePlan_e5058a08-9568-40d1-b37b-9a6bbab2e2e2" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised_a8b7bcee-36f0-4962-a653-10db1d9cc6a1" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_f8ce75c8-c4a3-402c-b835-e99e0a435d69" xlink:to="loc_us-gaap_StockIssuedDuringPeriodValueStockOptionsExercised_a8b7bcee-36f0-4962-a653-10db1d9cc6a1" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_IssuanceOfDeferredShares_567498ec-9e79-48db-9429-889d1d13f489" xlink:href="mtrx-20200630.xsd#mtrx_IssuanceOfDeferredShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_f8ce75c8-c4a3-402c-b835-e99e0a435d69" xlink:to="loc_mtrx_IssuanceOfDeferredShares_567498ec-9e79-48db-9429-889d1d13f489" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_OtherTreasurySharePurchases_b3ecb1db-e18c-4617-ad7e-13b1a60319b6" xlink:href="mtrx-20200630.xsd#mtrx_OtherTreasurySharePurchases"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_f8ce75c8-c4a3-402c-b835-e99e0a435d69" xlink:to="loc_mtrx_OtherTreasurySharePurchases_b3ecb1db-e18c-4617-ad7e-13b1a60319b6" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockValueAcquiredCostMethod_602df0c2-aba7-424d-8fe3-a59e82c84ae0" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_TreasuryStockValueAcquiredCostMethod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_f8ce75c8-c4a3-402c-b835-e99e0a435d69" xlink:to="loc_us-gaap_TreasuryStockValueAcquiredCostMethod_602df0c2-aba7-424d-8fe3-a59e82c84ae0" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_7de90efe-aeb9-4bd5-a04f-cab5ce436da8" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncreaseDecreaseInStockholdersEquityRollForward_f8ce75c8-c4a3-402c-b835-e99e0a435d69" xlink:to="loc_us-gaap_AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue_7de90efe-aeb9-4bd5-a04f-cab5ce436da8" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest_12ef8bce-feaf-42b2-9ea6-5edf6f64a2ec" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_279c080f-18e6-46e2-baf2-5d6ab68d5bee" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_45d801a7-f5fe-4313-9d31-0a40db8d1174" xlink:to="loc_us-gaap_StatementTable_279c080f-18e6-46e2-baf2-5d6ab68d5bee" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_f85e068e-3a2a-4124-9486-6df97683f0ce" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_279c080f-18e6-46e2-baf2-5d6ab68d5bee" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_f85e068e-3a2a-4124-9486-6df97683f0ce" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_f85e068e-3a2a-4124-9486-6df97683f0ce_default" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_f85e068e-3a2a-4124-9486-6df97683f0ce" xlink:to="loc_us-gaap_EquityComponentDomain_f85e068e-3a2a-4124-9486-6df97683f0ce_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_7032fad4-7b4a-4bc8-bfd5-9e8e00b43e2e" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_f85e068e-3a2a-4124-9486-6df97683f0ce" xlink:to="loc_us-gaap_EquityComponentDomain_7032fad4-7b4a-4bc8-bfd5-9e8e00b43e2e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_CommonStockMember_d33d0de5-3dbb-486f-90fb-b0236459de0c" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_CommonStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_7032fad4-7b4a-4bc8-bfd5-9e8e00b43e2e" xlink:to="loc_us-gaap_CommonStockMember_d33d0de5-3dbb-486f-90fb-b0236459de0c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdditionalPaidInCapitalMember_cb40af18-7011-40a6-8c18-dffe83572d5b" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_AdditionalPaidInCapitalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_7032fad4-7b4a-4bc8-bfd5-9e8e00b43e2e" xlink:to="loc_us-gaap_AdditionalPaidInCapitalMember_cb40af18-7011-40a6-8c18-dffe83572d5b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsMember_7d992b8f-16a3-4ca8-9cab-acebea391bbb" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_RetainedEarningsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_7032fad4-7b4a-4bc8-bfd5-9e8e00b43e2e" xlink:to="loc_us-gaap_RetainedEarningsMember_7d992b8f-16a3-4ca8-9cab-acebea391bbb" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockMember_99777144-6b66-4fd5-8034-114a112b2bdf" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_TreasuryStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_7032fad4-7b4a-4bc8-bfd5-9e8e00b43e2e" xlink:to="loc_us-gaap_TreasuryStockMember_99777144-6b66-4fd5-8034-114a112b2bdf" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_4828e4a1-e4a6-42e2-94dd-ea5952356917" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_AccumulatedOtherComprehensiveIncomeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_7032fad4-7b4a-4bc8-bfd5-9e8e00b43e2e" xlink:to="loc_us-gaap_AccumulatedOtherComprehensiveIncomeMember_4828e4a1-e4a6-42e2-94dd-ea5952356917" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoncontrollingInterestMember_612063f9-4f7d-497c-89da-de6c047ef7ac" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_NoncontrollingInterestMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_7032fad4-7b4a-4bc8-bfd5-9e8e00b43e2e" xlink:to="loc_us-gaap_NoncontrollingInterestMember_612063f9-4f7d-497c-89da-de6c047ef7ac" xlink:type="arc" order="5"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/ConsolidatedStatementsofChangesinStockholdersEquityParenthetical" xlink:type="simple" xlink:href="mtrx-20200630.xsd#ConsolidatedStatementsofChangesinStockholdersEquityParenthetical"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/ConsolidatedStatementsofChangesinStockholdersEquityParenthetical" xlink:type="extended" id="i45dd1ed445a44ad89235d462060b4d5e_ConsolidatedStatementsofChangesinStockholdersEquityParenthetical">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementLineItems_d95e2dc4-f472-41ec-8596-3b33f4af48b8" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_StatementLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans_077911e6-ac47-406e-8625-9720bb9697f8" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_d95e2dc4-f472-41ec-8596-3b33f4af48b8" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesEmployeeStockPurchasePlans_077911e6-ac47-406e-8625-9720bb9697f8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_7f945827-4e65-4048-a7fe-4312b0767a35" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_d95e2dc4-f472-41ec-8596-3b33f4af48b8" xlink:to="loc_us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised_7f945827-4e65-4048-a7fe-4312b0767a35" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_DeferredSharesIssued_20a29676-4fd7-429f-8f25-25e9c0fd7727" xlink:href="mtrx-20200630.xsd#mtrx_DeferredSharesIssued"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_d95e2dc4-f472-41ec-8596-3b33f4af48b8" xlink:to="loc_mtrx_DeferredSharesIssued_20a29676-4fd7-429f-8f25-25e9c0fd7727" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_OtherTreasurySharesAcquired_18d5e191-4f33-48b6-8155-da9f64dee3ab" xlink:href="mtrx-20200630.xsd#mtrx_OtherTreasurySharesAcquired"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_d95e2dc4-f472-41ec-8596-3b33f4af48b8" xlink:to="loc_mtrx_OtherTreasurySharesAcquired_18d5e191-4f33-48b6-8155-da9f64dee3ab" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockSharesAcquired_49c3765a-fdf0-47f4-8a8f-761c3898c662" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_TreasuryStockSharesAcquired"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_StatementLineItems_d95e2dc4-f472-41ec-8596-3b33f4af48b8" xlink:to="loc_us-gaap_TreasuryStockSharesAcquired_49c3765a-fdf0-47f4-8a8f-761c3898c662" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementTable_8f928296-620b-4677-971b-1ae3e5270419" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_StatementTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_StatementLineItems_d95e2dc4-f472-41ec-8596-3b33f4af48b8" xlink:to="loc_us-gaap_StatementTable_8f928296-620b-4677-971b-1ae3e5270419" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementEquityComponentsAxis_ed4cbb0d-3213-4283-85fa-30a19b84e673" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_StatementEquityComponentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_StatementTable_8f928296-620b-4677-971b-1ae3e5270419" xlink:to="loc_us-gaap_StatementEquityComponentsAxis_ed4cbb0d-3213-4283-85fa-30a19b84e673" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_ed4cbb0d-3213-4283-85fa-30a19b84e673_default" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_ed4cbb0d-3213-4283-85fa-30a19b84e673" xlink:to="loc_us-gaap_EquityComponentDomain_ed4cbb0d-3213-4283-85fa-30a19b84e673_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityComponentDomain_8ababa76-e588-45a5-bfbf-871fa232f093" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_EquityComponentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementEquityComponentsAxis_ed4cbb0d-3213-4283-85fa-30a19b84e673" xlink:to="loc_us-gaap_EquityComponentDomain_8ababa76-e588-45a5-bfbf-871fa232f093" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AdditionalPaidInCapitalMember_a3b900c0-0398-453e-b2f5-68c1ac1011cf" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_AdditionalPaidInCapitalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_8ababa76-e588-45a5-bfbf-871fa232f093" xlink:to="loc_us-gaap_AdditionalPaidInCapitalMember_a3b900c0-0398-453e-b2f5-68c1ac1011cf" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetainedEarningsMember_1ed75611-4dc9-49d3-bdba-5acb1cab5a2c" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_RetainedEarningsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_8ababa76-e588-45a5-bfbf-871fa232f093" xlink:to="loc_us-gaap_RetainedEarningsMember_1ed75611-4dc9-49d3-bdba-5acb1cab5a2c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TreasuryStockMember_0e13a253-0500-46f4-91fc-e87c1dd5efed" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_TreasuryStockMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityComponentDomain_8ababa76-e588-45a5-bfbf-871fa232f093" xlink:to="loc_us-gaap_TreasuryStockMember_0e13a253-0500-46f4-91fc-e87c1dd5efed" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/SummaryofSignificantAccountingPolicies" xlink:type="simple" xlink:href="mtrx-20200630.xsd#SummaryofSignificantAccountingPolicies"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/SummaryofSignificantAccountingPolicies" xlink:type="extended" id="i84729fbc699641b788ec63be670b9012_SummaryofSignificantAccountingPolicies"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/SummaryofSignificantAccountingPoliciesPolicies" xlink:type="simple" xlink:href="mtrx-20200630.xsd#SummaryofSignificantAccountingPoliciesPolicies"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/SummaryofSignificantAccountingPoliciesPolicies" xlink:type="extended" id="i8a057fd0ab654d9c8a2cc0c0cd9bc237_SummaryofSignificantAccountingPoliciesPolicies"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/SummaryofSignificantAccountingPoliciesDetailsTextual" xlink:type="simple" xlink:href="mtrx-20200630.xsd#SummaryofSignificantAccountingPoliciesDetailsTextual"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/SummaryofSignificantAccountingPoliciesDetailsTextual" xlink:type="extended" id="i69203bf87908422abfb84df1def6853c_SummaryofSignificantAccountingPoliciesDetailsTextual">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentLineItems_2c5028bb-f703-4bfe-934b-4eb0bee8206f" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_PropertyPlantAndEquipmentLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentUsefulLife_47dcb8e7-c115-46de-8a1c-744eb552819a" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_PropertyPlantAndEquipmentUsefulLife"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_2c5028bb-f703-4bfe-934b-4eb0bee8206f" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentUsefulLife_47dcb8e7-c115-46de-8a1c-744eb552819a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetUsefulLife_98ac1764-1283-4338-8496-f406ac34431a" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetUsefulLife"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_2c5028bb-f703-4bfe-934b-4eb0bee8206f" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetUsefulLife_98ac1764-1283-4338-8496-f406ac34431a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Cash_e990e867-e4fe-4e2c-940c-ef6f0b08014f" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_Cash"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_2c5028bb-f703-4bfe-934b-4eb0bee8206f" xlink:to="loc_us-gaap_Cash_e990e867-e4fe-4e2c-940c-ef6f0b08014f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_8a38f5f8-c6de-4506-9ed3-06db974dd4eb" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ScheduleOfPropertyPlantAndEquipmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentLineItems_2c5028bb-f703-4bfe-934b-4eb0bee8206f" xlink:to="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_8a38f5f8-c6de-4506-9ed3-06db974dd4eb" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementGeographicalAxis_fe0b6d19-8120-49ae-87a2-4e8d59a79929" xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_StatementGeographicalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_8a38f5f8-c6de-4506-9ed3-06db974dd4eb" xlink:to="loc_srt_StatementGeographicalAxis_fe0b6d19-8120-49ae-87a2-4e8d59a79929" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_fe0b6d19-8120-49ae-87a2-4e8d59a79929_default" xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_fe0b6d19-8120-49ae-87a2-4e8d59a79929" xlink:to="loc_srt_SegmentGeographicalDomain_fe0b6d19-8120-49ae-87a2-4e8d59a79929_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_04bbb93e-2d06-42b0-80ef-10ea7925c86b" xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_fe0b6d19-8120-49ae-87a2-4e8d59a79929" xlink:to="loc_srt_SegmentGeographicalDomain_04bbb93e-2d06-42b0-80ef-10ea7925c86b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_InternationalMember_b6bbe4e3-2bf2-4230-9420-b70c37a3747b" xlink:href="mtrx-20200630.xsd#mtrx_InternationalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_04bbb93e-2d06-42b0-80ef-10ea7925c86b" xlink:to="loc_mtrx_InternationalMember_b6bbe4e3-2bf2-4230-9420-b70c37a3747b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_26b33b21-ed6a-48fe-8171-63c411d9bb85" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_PropertyPlantAndEquipmentByTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_8a38f5f8-c6de-4506-9ed3-06db974dd4eb" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_26b33b21-ed6a-48fe-8171-63c411d9bb85" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_26b33b21-ed6a-48fe-8171-63c411d9bb85_default" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_26b33b21-ed6a-48fe-8171-63c411d9bb85" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_26b33b21-ed6a-48fe-8171-63c411d9bb85_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_6fec935b-b969-4552-b4d7-cc1464bd294c" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_PropertyPlantAndEquipmentTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentByTypeAxis_26b33b21-ed6a-48fe-8171-63c411d9bb85" xlink:to="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_6fec935b-b969-4552-b4d7-cc1464bd294c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BuildingMember_e8db80fc-70f9-438e-a3a9-de19c52d25f1" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_BuildingMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_6fec935b-b969-4552-b4d7-cc1464bd294c" xlink:to="loc_us-gaap_BuildingMember_e8db80fc-70f9-438e-a3a9-de19c52d25f1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquipmentMember_97bf2f82-cb90-47f3-8224-27d70d646351" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_EquipmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_6fec935b-b969-4552-b4d7-cc1464bd294c" xlink:to="loc_us-gaap_EquipmentMember_97bf2f82-cb90-47f3-8224-27d70d646351" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TransportationEquipmentMember_0f18ecd9-7912-46c2-9f50-cdc33c90a372" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_TransportationEquipmentMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_6fec935b-b969-4552-b4d7-cc1464bd294c" xlink:to="loc_us-gaap_TransportationEquipmentMember_0f18ecd9-7912-46c2-9f50-cdc33c90a372" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FurnitureAndFixturesMember_7de9ed05-fcc2-431b-89c1-8a9aa4fe8fc8" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_FurnitureAndFixturesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PropertyPlantAndEquipmentTypeDomain_6fec935b-b969-4552-b4d7-cc1464bd294c" xlink:to="loc_us-gaap_FurnitureAndFixturesMember_7de9ed05-fcc2-431b-89c1-8a9aa4fe8fc8" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_23886da7-9b4c-4c64-9481-e409b6476a4b" xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfPropertyPlantAndEquipmentTable_8a38f5f8-c6de-4506-9ed3-06db974dd4eb" xlink:to="loc_srt_RangeAxis_23886da7-9b4c-4c64-9481-e409b6476a4b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_23886da7-9b4c-4c64-9481-e409b6476a4b_default" xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_23886da7-9b4c-4c64-9481-e409b6476a4b" xlink:to="loc_srt_RangeMember_23886da7-9b4c-4c64-9481-e409b6476a4b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_9a9ad1b7-a662-472a-b240-df0aaead07e3" xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_23886da7-9b4c-4c64-9481-e409b6476a4b" xlink:to="loc_srt_RangeMember_9a9ad1b7-a662-472a-b240-df0aaead07e3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_c3f9b6cb-e319-4857-a4bc-18ac3079d442" xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_9a9ad1b7-a662-472a-b240-df0aaead07e3" xlink:to="loc_srt_MinimumMember_c3f9b6cb-e319-4857-a4bc-18ac3079d442" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_a07323b4-0a79-4345-871a-e72d993469fd" xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_9a9ad1b7-a662-472a-b240-df0aaead07e3" xlink:to="loc_srt_MaximumMember_a07323b4-0a79-4345-871a-e72d993469fd" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/Revenue" xlink:type="simple" xlink:href="mtrx-20200630.xsd#Revenue"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/Revenue" xlink:type="extended" id="i1e884e539d9e481b81860c2fc221324c_Revenue"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/RevenueTables" xlink:type="simple" xlink:href="mtrx-20200630.xsd#RevenueTables"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/RevenueTables" xlink:type="extended" id="i62a905cccb3149aa8dcce28dca049e02_RevenueTables"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/RevenueDetails" xlink:type="simple" xlink:href="mtrx-20200630.xsd#RevenueDetails"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/RevenueDetails" xlink:type="extended" id="i66de19ee0a5e427384d1ecd4b4c34028_RevenueDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueLineItems_70638197-57d4-4e5c-a66c-6231b7a83cb1" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_DisaggregationOfRevenueLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax_a1c3f0b7-ced0-4e3b-975c-4d5217f8f75f" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_70638197-57d4-4e5c-a66c-6231b7a83cb1" xlink:to="loc_us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax_a1c3f0b7-ced0-4e3b-975c-4d5217f8f75f" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueTable_a5f04f61-d464-4750-b680-99cdf170f458" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_DisaggregationOfRevenueTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_DisaggregationOfRevenueLineItems_70638197-57d4-4e5c-a66c-6231b7a83cb1" xlink:to="loc_us-gaap_DisaggregationOfRevenueTable_a5f04f61-d464-4750-b680-99cdf170f458" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductOrServiceAxis_fd6c343b-0d26-447a-ab95-9ae549b0d927" xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_ProductOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_a5f04f61-d464-4750-b680-99cdf170f458" xlink:to="loc_srt_ProductOrServiceAxis_fd6c343b-0d26-447a-ab95-9ae549b0d927" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_fd6c343b-0d26-447a-ab95-9ae549b0d927_default" xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ProductOrServiceAxis_fd6c343b-0d26-447a-ab95-9ae549b0d927" xlink:to="loc_srt_ProductsAndServicesDomain_fd6c343b-0d26-447a-ab95-9ae549b0d927_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ProductsAndServicesDomain_9a3f8f30-01d5-440b-95ea-68a23b708c40" xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_ProductsAndServicesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ProductOrServiceAxis_fd6c343b-0d26-447a-ab95-9ae549b0d927" xlink:to="loc_srt_ProductsAndServicesDomain_9a3f8f30-01d5-440b-95ea-68a23b708c40" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementGeographicalAxis_12c12a57-7b15-4ca4-88b7-d610e8bddaaf" xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_StatementGeographicalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_a5f04f61-d464-4750-b680-99cdf170f458" xlink:to="loc_srt_StatementGeographicalAxis_12c12a57-7b15-4ca4-88b7-d610e8bddaaf" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_12c12a57-7b15-4ca4-88b7-d610e8bddaaf_default" xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_12c12a57-7b15-4ca4-88b7-d610e8bddaaf" xlink:to="loc_srt_SegmentGeographicalDomain_12c12a57-7b15-4ca4-88b7-d610e8bddaaf_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_57700ab6-c771-45ee-9e7a-0bd17fd17074" xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_12c12a57-7b15-4ca4-88b7-d610e8bddaaf" xlink:to="loc_srt_SegmentGeographicalDomain_57700ab6-c771-45ee-9e7a-0bd17fd17074" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_US_95cc5837-c97a-4461-a943-98c4c8fd58dd" xlink:href="https://xbrl.sec.gov/country/2020/country-2020-01-31.xsd#country_US"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_57700ab6-c771-45ee-9e7a-0bd17fd17074" xlink:to="loc_country_US_95cc5837-c97a-4461-a943-98c4c8fd58dd" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_CA_7a70a291-6378-4dad-ada2-4d574e238473" xlink:href="https://xbrl.sec.gov/country/2020/country-2020-01-31.xsd#country_CA"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_57700ab6-c771-45ee-9e7a-0bd17fd17074" xlink:to="loc_country_CA_7a70a291-6378-4dad-ada2-4d574e238473" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_OtherinternationalMember_20c24126-d3a7-4904-93f4-cc64c1d59f9c" xlink:href="mtrx-20200630.xsd#mtrx_OtherinternationalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_57700ab6-c771-45ee-9e7a-0bd17fd17074" xlink:to="loc_mtrx_OtherinternationalMember_20c24126-d3a7-4904-93f4-cc64c1d59f9c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractWithCustomerBasisOfPricingAxis_d762957e-eee3-468a-b564-d954e571bc44" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ContractWithCustomerBasisOfPricingAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_a5f04f61-d464-4750-b680-99cdf170f458" xlink:to="loc_us-gaap_ContractWithCustomerBasisOfPricingAxis_d762957e-eee3-468a-b564-d954e571bc44" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractWithCustomerBasisOfPricingDomain_d762957e-eee3-468a-b564-d954e571bc44_default" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ContractWithCustomerBasisOfPricingDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ContractWithCustomerBasisOfPricingAxis_d762957e-eee3-468a-b564-d954e571bc44" xlink:to="loc_us-gaap_ContractWithCustomerBasisOfPricingDomain_d762957e-eee3-468a-b564-d954e571bc44_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractWithCustomerBasisOfPricingDomain_5ad938ad-038e-4c5c-a064-fba64060e13a" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ContractWithCustomerBasisOfPricingDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ContractWithCustomerBasisOfPricingAxis_d762957e-eee3-468a-b564-d954e571bc44" xlink:to="loc_us-gaap_ContractWithCustomerBasisOfPricingDomain_5ad938ad-038e-4c5c-a064-fba64060e13a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractWithCustomerDurationAxis_770a49ee-54d5-42d7-a986-50761ab4cca4" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ContractWithCustomerDurationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_a5f04f61-d464-4750-b680-99cdf170f458" xlink:to="loc_us-gaap_ContractWithCustomerDurationAxis_770a49ee-54d5-42d7-a986-50761ab4cca4" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractWithCustomerDurationDomain_770a49ee-54d5-42d7-a986-50761ab4cca4_default" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ContractWithCustomerDurationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ContractWithCustomerDurationAxis_770a49ee-54d5-42d7-a986-50761ab4cca4" xlink:to="loc_us-gaap_ContractWithCustomerDurationDomain_770a49ee-54d5-42d7-a986-50761ab4cca4_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractWithCustomerDurationDomain_413f7672-0166-4b7f-9628-b3301b346972" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ContractWithCustomerDurationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ContractWithCustomerDurationAxis_770a49ee-54d5-42d7-a986-50761ab4cca4" xlink:to="loc_us-gaap_ContractWithCustomerDurationDomain_413f7672-0166-4b7f-9628-b3301b346972" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TimingOfTransferOfGoodOrServiceAxis_4b4f59d7-a5bf-4c62-a15a-08edb5462a11" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_TimingOfTransferOfGoodOrServiceAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_a5f04f61-d464-4750-b680-99cdf170f458" xlink:to="loc_us-gaap_TimingOfTransferOfGoodOrServiceAxis_4b4f59d7-a5bf-4c62-a15a-08edb5462a11" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TimingOfTransferOfGoodOrServiceDomain_4b4f59d7-a5bf-4c62-a15a-08edb5462a11_default" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_TimingOfTransferOfGoodOrServiceDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_TimingOfTransferOfGoodOrServiceAxis_4b4f59d7-a5bf-4c62-a15a-08edb5462a11" xlink:to="loc_us-gaap_TimingOfTransferOfGoodOrServiceDomain_4b4f59d7-a5bf-4c62-a15a-08edb5462a11_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TimingOfTransferOfGoodOrServiceDomain_07de1c62-7214-439f-b0b5-ed2086cd4fc7" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_TimingOfTransferOfGoodOrServiceDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_TimingOfTransferOfGoodOrServiceAxis_4b4f59d7-a5bf-4c62-a15a-08edb5462a11" xlink:to="loc_us-gaap_TimingOfTransferOfGoodOrServiceDomain_07de1c62-7214-439f-b0b5-ed2086cd4fc7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractWithCustomerSalesChannelAxis_d337fe91-f7a8-486b-b6f0-9ea927a54a2a" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ContractWithCustomerSalesChannelAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_a5f04f61-d464-4750-b680-99cdf170f458" xlink:to="loc_us-gaap_ContractWithCustomerSalesChannelAxis_d337fe91-f7a8-486b-b6f0-9ea927a54a2a" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractWithCustomerSalesChannelDomain_d337fe91-f7a8-486b-b6f0-9ea927a54a2a_default" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ContractWithCustomerSalesChannelDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ContractWithCustomerSalesChannelAxis_d337fe91-f7a8-486b-b6f0-9ea927a54a2a" xlink:to="loc_us-gaap_ContractWithCustomerSalesChannelDomain_d337fe91-f7a8-486b-b6f0-9ea927a54a2a_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractWithCustomerSalesChannelDomain_917b4466-b4da-48c3-80b2-0486778c473c" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ContractWithCustomerSalesChannelDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ContractWithCustomerSalesChannelAxis_d337fe91-f7a8-486b-b6f0-9ea927a54a2a" xlink:to="loc_us-gaap_ContractWithCustomerSalesChannelDomain_917b4466-b4da-48c3-80b2-0486778c473c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MajorCustomersAxis_839a3b74-cb17-459e-a9f3-5c87eed0d359" xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_MajorCustomersAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_DisaggregationOfRevenueTable_a5f04f61-d464-4750-b680-99cdf170f458" xlink:to="loc_srt_MajorCustomersAxis_839a3b74-cb17-459e-a9f3-5c87eed0d359" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_NameOfMajorCustomerDomain_839a3b74-cb17-459e-a9f3-5c87eed0d359_default" xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_NameOfMajorCustomerDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_MajorCustomersAxis_839a3b74-cb17-459e-a9f3-5c87eed0d359" xlink:to="loc_srt_NameOfMajorCustomerDomain_839a3b74-cb17-459e-a9f3-5c87eed0d359_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_NameOfMajorCustomerDomain_a4e14f60-2e9d-4ac0-bb34-11d3d3d15fbe" xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_NameOfMajorCustomerDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_MajorCustomersAxis_839a3b74-cb17-459e-a9f3-5c87eed0d359" xlink:to="loc_srt_NameOfMajorCustomerDomain_a4e14f60-2e9d-4ac0-bb34-11d3d3d15fbe" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueLineItems_512cb98c-5b26-4fb1-b27b-b7a53adc5793" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_DisaggregationOfRevenueLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax_07671215-08b7-4280-9e5d-b84dcefe5450" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_RevenueFromContractWithCustomerIncludingAssessedTax"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DisaggregationOfRevenueTable_e6efd7db-5691-4833-85ea-9491772edbcb" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_DisaggregationOfRevenueTable"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractWithCustomerBasisOfPricingAxis_e326ecf2-ad5b-492e-85df-7be7ea7bc8ce" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ContractWithCustomerBasisOfPricingAxis"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractWithCustomerBasisOfPricingDomain_e326ecf2-ad5b-492e-85df-7be7ea7bc8ce_default" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ContractWithCustomerBasisOfPricingDomain"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ContractWithCustomerBasisOfPricingDomain_6455da56-6674-492d-8f0f-c40625a7edc4" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ContractWithCustomerBasisOfPricingDomain"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FixedPriceContractMember_42827012-3f1e-46ae-9cc7-3a06e8e6550b" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_FixedPriceContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ContractWithCustomerBasisOfPricingDomain_6455da56-6674-492d-8f0f-c40625a7edc4" xlink:to="loc_us-gaap_FixedPriceContractMember_42827012-3f1e-46ae-9cc7-3a06e8e6550b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TimeAndMaterialsContractMember_46cd3d0b-ed7d-4fa5-b3c5-e444af635a09" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_TimeAndMaterialsContractMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ContractWithCustomerBasisOfPricingDomain_6455da56-6674-492d-8f0f-c40625a7edc4" xlink:to="loc_us-gaap_TimeAndMaterialsContractMember_46cd3d0b-ed7d-4fa5-b3c5-e444af635a09" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/AcquisitionsandDisposals" xlink:type="simple" xlink:href="mtrx-20200630.xsd#AcquisitionsandDisposals"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/AcquisitionsandDisposals" xlink:type="extended" id="i4cf665ec846341a09afc692a7c4a5971_AcquisitionsandDisposals"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/AcquisitionsandDisposalsTables" xlink:type="simple" xlink:href="mtrx-20200630.xsd#AcquisitionsandDisposalsTables"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/AcquisitionsandDisposalsTables" xlink:type="extended" id="if6442d15ddda4f5baaf4d71074dd7402_AcquisitionsandDisposalsTables">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionLineItems_f6ebab2a-d608-41e9-a020-588be903d793" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_BusinessAcquisitionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_ConsiderationtransferredTableTextBlock_4dca0bbc-2dbb-4d33-bbfc-7cedf481cf45" xlink:href="mtrx-20200630.xsd#mtrx_ConsiderationtransferredTableTextBlock"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_f6ebab2a-d608-41e9-a020-588be903d793" xlink:to="loc_mtrx_ConsiderationtransferredTableTextBlock_4dca0bbc-2dbb-4d33-bbfc-7cedf481cf45" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTableTextBlock_b437a2c4-e204-419c-b958-87458aea5b46" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTableTextBlock"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_f6ebab2a-d608-41e9-a020-588be903d793" xlink:to="loc_us-gaap_ScheduleOfRecognizedIdentifiedAssetsAcquiredAndLiabilitiesAssumedTableTextBlock_b437a2c4-e204-419c-b958-87458aea5b46" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionProFormaInformationTextBlock_14165b5c-1e24-43c1-ae0d-317c13bf8456" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_BusinessAcquisitionProFormaInformationTextBlock"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_f6ebab2a-d608-41e9-a020-588be903d793" xlink:to="loc_us-gaap_BusinessAcquisitionProFormaInformationTextBlock_14165b5c-1e24-43c1-ae0d-317c13bf8456" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_ac12fa6e-aef3-42a4-804e-9890d3bcd095" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_f6ebab2a-d608-41e9-a020-588be903d793" xlink:to="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_ac12fa6e-aef3-42a4-804e-9890d3bcd095" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_f26b9a23-183d-4a2d-aa66-957516e52a16" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_ac12fa6e-aef3-42a4-804e-9890d3bcd095" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_f26b9a23-183d-4a2d-aa66-957516e52a16" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_f26b9a23-183d-4a2d-aa66-957516e52a16_default" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_f26b9a23-183d-4a2d-aa66-957516e52a16" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_f26b9a23-183d-4a2d-aa66-957516e52a16_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_846b8449-b618-494b-b63c-bfbbc2af8846" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_f26b9a23-183d-4a2d-aa66-957516e52a16" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_846b8449-b618-494b-b63c-bfbbc2af8846" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_HoustonInterestsLLCMember_045fe320-bba6-414d-a76c-aafac1c8084c" xlink:href="mtrx-20200630.xsd#mtrx_HoustonInterestsLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_846b8449-b618-494b-b63c-bfbbc2af8846" xlink:to="loc_mtrx_HoustonInterestsLLCMember_045fe320-bba6-414d-a76c-aafac1c8084c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_BaillieTankEquipmentLtd.Member_710e0709-7f76-4343-8d8e-c2986f93e9c4" xlink:href="mtrx-20200630.xsd#mtrx_BaillieTankEquipmentLtd.Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_846b8449-b618-494b-b63c-bfbbc2af8846" xlink:to="loc_mtrx_BaillieTankEquipmentLtd.Member_710e0709-7f76-4343-8d8e-c2986f93e9c4" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/AcquisitionsandDisposalsDetailsTextual" xlink:type="simple" xlink:href="mtrx-20200630.xsd#AcquisitionsandDisposalsDetailsTextual"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/AcquisitionsandDisposalsDetailsTextual" xlink:type="extended" id="i51d96ef6c89f41f8b10f7a5d59459321_AcquisitionsandDisposalsDetailsTextual">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionLineItems_0ed24555-bf9f-46f9-bd5c-fe53886c761f" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_BusinessAcquisitionLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ProceedsFromDivestitureOfBusinesses_25636873-c153-4dc6-ac12-ffa3a181e0b1" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ProceedsFromDivestitureOfBusinesses"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0ed24555-bf9f-46f9-bd5c-fe53886c761f" xlink:to="loc_us-gaap_ProceedsFromDivestitureOfBusinesses_25636873-c153-4dc6-ac12-ffa3a181e0b1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_AcquisitionRelatedAdjustmentForFinalWorkingCapitalSettlement_f581dd50-1f15-4da4-b829-c841ec11c244" xlink:href="mtrx-20200630.xsd#mtrx_AcquisitionRelatedAdjustmentForFinalWorkingCapitalSettlement"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0ed24555-bf9f-46f9-bd5c-fe53886c761f" xlink:to="loc_mtrx_AcquisitionRelatedAdjustmentForFinalWorkingCapitalSettlement_f581dd50-1f15-4da4-b829-c841ec11c244" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GainLossOnSaleOfBusiness_d547e9a0-67d5-4990-8cfa-295ae707bf4b" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_GainLossOnSaleOfBusiness"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0ed24555-bf9f-46f9-bd5c-fe53886c761f" xlink:to="loc_us-gaap_GainLossOnSaleOfBusiness_d547e9a0-67d5-4990-8cfa-295ae707bf4b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationConsiderationTransferred1_4e847f44-e5ea-40ff-b546-7f049c55a1fd" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_BusinessCombinationConsiderationTransferred1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0ed24555-bf9f-46f9-bd5c-fe53886c761f" xlink:to="loc_us-gaap_BusinessCombinationConsiderationTransferred1_4e847f44-e5ea-40ff-b546-7f049c55a1fd" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionEffectiveDateOfAcquisition1_5c2281ca-c3d4-42b6-a158-2b2debb70be8" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_BusinessAcquisitionEffectiveDateOfAcquisition1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0ed24555-bf9f-46f9-bd5c-fe53886c761f" xlink:to="loc_us-gaap_BusinessAcquisitionEffectiveDateOfAcquisition1_5c2281ca-c3d4-42b6-a158-2b2debb70be8" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionPercentageOfVotingInterestsAcquired_ef0cfc8d-0690-4129-bb23-eaf01e75dc25" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_BusinessAcquisitionPercentageOfVotingInterestsAcquired"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0ed24555-bf9f-46f9-bd5c-fe53886c761f" xlink:to="loc_us-gaap_BusinessAcquisitionPercentageOfVotingInterestsAcquired_ef0cfc8d-0690-4129-bb23-eaf01e75dc25" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet_27bd6f56-53eb-49f3-9cbb-9b93589818c6" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0ed24555-bf9f-46f9-bd5c-fe53886c761f" xlink:to="loc_us-gaap_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNet_27bd6f56-53eb-49f3-9cbb-9b93589818c6" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_Economicpurchaseprice_faa1073f-a162-47cc-aaf7-8b5d2bafe9ea" xlink:href="mtrx-20200630.xsd#mtrx_Economicpurchaseprice"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0ed24555-bf9f-46f9-bd5c-fe53886c761f" xlink:to="loc_mtrx_Economicpurchaseprice_faa1073f-a162-47cc-aaf7-8b5d2bafe9ea" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionPurchasePriceAllocationGoodwillExpectedTaxDeductibleAmount_811fbc37-0ca4-40d0-ab3d-a3c19aeccb2a" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_BusinessAcquisitionPurchasePriceAllocationGoodwillExpectedTaxDeductibleAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0ed24555-bf9f-46f9-bd5c-fe53886c761f" xlink:to="loc_us-gaap_BusinessAcquisitionPurchasePriceAllocationGoodwillExpectedTaxDeductibleAmount_811fbc37-0ca4-40d0-ab3d-a3c19aeccb2a" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityMethodInvestmentOwnershipPercentage_2fd89917-51c8-4ea1-92fc-391c1d039577" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_EquityMethodInvestmentOwnershipPercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0ed24555-bf9f-46f9-bd5c-fe53886c761f" xlink:to="loc_us-gaap_EquityMethodInvestmentOwnershipPercentage_2fd89917-51c8-4ea1-92fc-391c1d039577" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_Mtrx_JointVentureValue_20a1ce09-756a-490b-9784-54edb1513c7e" xlink:href="mtrx-20200630.xsd#mtrx_Mtrx_JointVentureValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0ed24555-bf9f-46f9-bd5c-fe53886c761f" xlink:to="loc_mtrx_Mtrx_JointVentureValue_20a1ce09-756a-490b-9784-54edb1513c7e" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_Mtrx_ControllingInterestOfJointVentureValue_70d7045a-76ae-4ade-9cf6-425447f0bb3c" xlink:href="mtrx-20200630.xsd#mtrx_Mtrx_ControllingInterestOfJointVentureValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0ed24555-bf9f-46f9-bd5c-fe53886c761f" xlink:to="loc_mtrx_Mtrx_ControllingInterestOfJointVentureValue_70d7045a-76ae-4ade-9cf6-425447f0bb3c" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MinorityInterestInJointVentures_e45ebd23-d1a7-4cdf-9839-57524e0a7c4f" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_MinorityInterestInJointVentures"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0ed24555-bf9f-46f9-bd5c-fe53886c761f" xlink:to="loc_us-gaap_MinorityInterestInJointVentures_e45ebd23-d1a7-4cdf-9839-57524e0a7c4f" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_Warrantyreserveworkingcapitalprovision_6908b857-2cdd-48e3-b7bf-3d4643df0b3e" xlink:href="mtrx-20200630.xsd#mtrx_Warrantyreserveworkingcapitalprovision"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0ed24555-bf9f-46f9-bd5c-fe53886c761f" xlink:to="loc_mtrx_Warrantyreserveworkingcapitalprovision_6908b857-2cdd-48e3-b7bf-3d4643df0b3e" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_Settlementofwarrantyreserve_2970aece-a267-42a4-820b-acda2a004dfc" xlink:href="mtrx-20200630.xsd#mtrx_Settlementofwarrantyreserve"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0ed24555-bf9f-46f9-bd5c-fe53886c761f" xlink:to="loc_mtrx_Settlementofwarrantyreserve_2970aece-a267-42a4-820b-acda2a004dfc" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsAdditionalDisclosuresAcquisitionCostExpensed_90883961-3974-4c25-ba2b-438cc909d066" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsAdditionalDisclosuresAcquisitionCostExpensed"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0ed24555-bf9f-46f9-bd5c-fe53886c761f" xlink:to="loc_us-gaap_BusinessCombinationSeparatelyRecognizedTransactionsAdditionalDisclosuresAcquisitionCostExpensed_90883961-3974-4c25-ba2b-438cc909d066" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationProFormaInformationRevenueOfAcquireeSinceAcquisitionDateActual_2931c21b-8b4e-4766-8b36-2f7d3a843758" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_BusinessCombinationProFormaInformationRevenueOfAcquireeSinceAcquisitionDateActual"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0ed24555-bf9f-46f9-bd5c-fe53886c761f" xlink:to="loc_us-gaap_BusinessCombinationProFormaInformationRevenueOfAcquireeSinceAcquisitionDateActual_2931c21b-8b4e-4766-8b36-2f7d3a843758" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessCombinationProFormaInformationEarningsOrLossOfAcquireeSinceAcquisitionDateActual_864cff35-f6ce-44ed-9792-82ee96da10c3" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_BusinessCombinationProFormaInformationEarningsOrLossOfAcquireeSinceAcquisitionDateActual"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0ed24555-bf9f-46f9-bd5c-fe53886c761f" xlink:to="loc_us-gaap_BusinessCombinationProFormaInformationEarningsOrLossOfAcquireeSinceAcquisitionDateActual_864cff35-f6ce-44ed-9792-82ee96da10c3" xlink:type="arc" order="17"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_BusinessAcquisitionProFormaAmortizationofIntangibleAssets_f459ffaa-17fd-4213-a2ec-0f0645192164" xlink:href="mtrx-20200630.xsd#mtrx_BusinessAcquisitionProFormaAmortizationofIntangibleAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0ed24555-bf9f-46f9-bd5c-fe53886c761f" xlink:to="loc_mtrx_BusinessAcquisitionProFormaAmortizationofIntangibleAssets_f459ffaa-17fd-4213-a2ec-0f0645192164" xlink:type="arc" order="18"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_BusinessAcquisitionProFormaDepreciationExpense_e2aef814-ef12-4e8f-8129-086553526a35" xlink:href="mtrx-20200630.xsd#mtrx_BusinessAcquisitionProFormaDepreciationExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0ed24555-bf9f-46f9-bd5c-fe53886c761f" xlink:to="loc_mtrx_BusinessAcquisitionProFormaDepreciationExpense_e2aef814-ef12-4e8f-8129-086553526a35" xlink:type="arc" order="19"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_BusinessAcquisitionProFormaIncomefromTaxSettlement_6197fd99-364a-4c03-82c3-527929a5371c" xlink:href="mtrx-20200630.xsd#mtrx_BusinessAcquisitionProFormaIncomefromTaxSettlement"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0ed24555-bf9f-46f9-bd5c-fe53886c761f" xlink:to="loc_mtrx_BusinessAcquisitionProFormaIncomefromTaxSettlement_6197fd99-364a-4c03-82c3-527929a5371c" xlink:type="arc" order="20"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_d7e3e291-6f16-4faf-b137-956b0ce59b99" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_BusinessAcquisitionLineItems_0ed24555-bf9f-46f9-bd5c-fe53886c761f" xlink:to="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_d7e3e291-6f16-4faf-b137-956b0ce59b99" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_bf2feb9d-3133-4c71-860e-6159d7dbe8a9" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfBusinessAcquisitionsByAcquisitionTable_d7e3e291-6f16-4faf-b137-956b0ce59b99" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_bf2feb9d-3133-4c71-860e-6159d7dbe8a9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_bf2feb9d-3133-4c71-860e-6159d7dbe8a9_default" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_bf2feb9d-3133-4c71-860e-6159d7dbe8a9" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_bf2feb9d-3133-4c71-860e-6159d7dbe8a9_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_f4afd46d-223b-4ff3-898c-30ef5b2301bf" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_bf2feb9d-3133-4c71-860e-6159d7dbe8a9" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_f4afd46d-223b-4ff3-898c-30ef5b2301bf" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_HoustonInterestsLLCMember_fc4db24e-0534-4dc0-9f2a-4d0fcfc00d22" xlink:href="mtrx-20200630.xsd#mtrx_HoustonInterestsLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_f4afd46d-223b-4ff3-898c-30ef5b2301bf" xlink:to="loc_mtrx_HoustonInterestsLLCMember_fc4db24e-0534-4dc0-9f2a-4d0fcfc00d22" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_BaillieTankEquipmentLtd.Member_c845d9cd-32e7-46c4-916f-2b64581c5e8e" xlink:href="mtrx-20200630.xsd#mtrx_BaillieTankEquipmentLtd.Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_f4afd46d-223b-4ff3-898c-30ef5b2301bf" xlink:to="loc_mtrx_BaillieTankEquipmentLtd.Member_c845d9cd-32e7-46c4-916f-2b64581c5e8e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_HDBInc.Member_fa10228e-a26d-4940-a32f-85ea09f92e89" xlink:href="mtrx-20200630.xsd#mtrx_HDBInc.Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_f4afd46d-223b-4ff3-898c-30ef5b2301bf" xlink:to="loc_mtrx_HDBInc.Member_fa10228e-a26d-4940-a32f-85ea09f92e89" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_KvaernerNorthAmericanConstructionMember_f8be4dd8-d40d-4258-850a-7f499f77babd" xlink:href="mtrx-20200630.xsd#mtrx_KvaernerNorthAmericanConstructionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_f4afd46d-223b-4ff3-898c-30ef5b2301bf" xlink:to="loc_mtrx_KvaernerNorthAmericanConstructionMember_f8be4dd8-d40d-4258-850a-7f499f77babd" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_ProcessHeatingEquipmentBusinessMember_d6e14616-0c44-43a4-97ea-5d7defa09865" xlink:href="mtrx-20200630.xsd#mtrx_ProcessHeatingEquipmentBusinessMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_f4afd46d-223b-4ff3-898c-30ef5b2301bf" xlink:to="loc_mtrx_ProcessHeatingEquipmentBusinessMember_d6e14616-0c44-43a4-97ea-5d7defa09865" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/GoodwillandOtherIntangibleAssets" xlink:type="simple" xlink:href="mtrx-20200630.xsd#GoodwillandOtherIntangibleAssets"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/GoodwillandOtherIntangibleAssets" xlink:type="extended" id="i58bc240341b54bb4a0f1c97beda6f11b_GoodwillandOtherIntangibleAssets"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/GoodwillandOtherIntangibleAssetsTables" xlink:type="simple" xlink:href="mtrx-20200630.xsd#GoodwillandOtherIntangibleAssetsTables"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/GoodwillandOtherIntangibleAssetsTables" xlink:type="extended" id="if36f2e09ca634ad096aa8879990fea30_GoodwillandOtherIntangibleAssetsTables"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/GoodwillandOtherIntangibleAssetsDetails" xlink:type="simple" xlink:href="mtrx-20200630.xsd#GoodwillandOtherIntangibleAssetsDetails"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/GoodwillandOtherIntangibleAssetsDetails" xlink:type="extended" id="i7cd638e1f339444cbecbf8d87d43f94f_GoodwillandOtherIntangibleAssetsDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillLineItems_99466201-8d81-48ec-8fd7-15957ea5f3d0" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_GoodwillLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillRollForward_40ddd326-3817-44a4-8177-37cbe931570a" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_GoodwillRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GoodwillLineItems_99466201-8d81-48ec-8fd7-15957ea5f3d0" xlink:to="loc_us-gaap_GoodwillRollForward_40ddd326-3817-44a4-8177-37cbe931570a" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Goodwill_30be4e30-7c4d-47be-8205-81d5c07ed36b" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_Goodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GoodwillRollForward_40ddd326-3817-44a4-8177-37cbe931570a" xlink:to="loc_us-gaap_Goodwill_30be4e30-7c4d-47be-8205-81d5c07ed36b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillImpairmentLoss_a81af60f-0924-4960-8767-202146eba7cb" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_GoodwillImpairmentLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GoodwillRollForward_40ddd326-3817-44a4-8177-37cbe931570a" xlink:to="loc_us-gaap_GoodwillImpairmentLoss_a81af60f-0924-4960-8767-202146eba7cb" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillWrittenOffRelatedToSaleOfBusinessUnit_02a6e7c1-5407-4ea5-a126-2abe0ff5252e" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_GoodwillWrittenOffRelatedToSaleOfBusinessUnit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GoodwillRollForward_40ddd326-3817-44a4-8177-37cbe931570a" xlink:to="loc_us-gaap_GoodwillWrittenOffRelatedToSaleOfBusinessUnit_02a6e7c1-5407-4ea5-a126-2abe0ff5252e" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GoodwillForeignCurrencyTranslationGainLoss_f09eb368-ae49-46a3-97c9-0132ddac46f5" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_GoodwillForeignCurrencyTranslationGainLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GoodwillRollForward_40ddd326-3817-44a4-8177-37cbe931570a" xlink:to="loc_us-gaap_GoodwillForeignCurrencyTranslationGainLoss_f09eb368-ae49-46a3-97c9-0132ddac46f5" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Goodwill_4a082312-0030-44a5-9ad7-3569b30965f4" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_Goodwill"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_GoodwillAttributableToReportingUnitsAtRiskForImpairment_ffc80908-2886-4545-89da-0103e7d4ff77" xlink:href="mtrx-20200630.xsd#mtrx_GoodwillAttributableToReportingUnitsAtRiskForImpairment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_GoodwillRollForward_40ddd326-3817-44a4-8177-37cbe931570a" xlink:to="loc_mtrx_GoodwillAttributableToReportingUnitsAtRiskForImpairment_ffc80908-2886-4545-89da-0103e7d4ff77" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfGoodwillTable_16099472-c7cb-4435-ad30-1d697116fd1b" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ScheduleOfGoodwillTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_GoodwillLineItems_99466201-8d81-48ec-8fd7-15957ea5f3d0" xlink:to="loc_us-gaap_ScheduleOfGoodwillTable_16099472-c7cb-4435-ad30-1d697116fd1b" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_3d0fd4d7-6beb-4235-b492-ae1d74f5bc72" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfGoodwillTable_16099472-c7cb-4435-ad30-1d697116fd1b" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_3d0fd4d7-6beb-4235-b492-ae1d74f5bc72" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_3d0fd4d7-6beb-4235-b492-ae1d74f5bc72_default" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_3d0fd4d7-6beb-4235-b492-ae1d74f5bc72" xlink:to="loc_us-gaap_SegmentDomain_3d0fd4d7-6beb-4235-b492-ae1d74f5bc72_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_d19af9c9-7c79-4769-8bca-a667174adddd" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_3d0fd4d7-6beb-4235-b492-ae1d74f5bc72" xlink:to="loc_us-gaap_SegmentDomain_d19af9c9-7c79-4769-8bca-a667174adddd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_ElectricalInfrastructureMember_2d9e83dd-8dee-430b-ab64-c38af663a9fc" xlink:href="mtrx-20200630.xsd#mtrx_ElectricalInfrastructureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_d19af9c9-7c79-4769-8bca-a667174adddd" xlink:to="loc_mtrx_ElectricalInfrastructureMember_2d9e83dd-8dee-430b-ab64-c38af663a9fc" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_OilGasAndChemicalMember_af2799f5-fa80-4731-ad92-c5efbc0acc77" xlink:href="mtrx-20200630.xsd#mtrx_OilGasAndChemicalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_d19af9c9-7c79-4769-8bca-a667174adddd" xlink:to="loc_mtrx_OilGasAndChemicalMember_af2799f5-fa80-4731-ad92-c5efbc0acc77" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_StorageSolutionsMember_80149c79-d06c-475f-9419-3ca0614baf8d" xlink:href="mtrx-20200630.xsd#mtrx_StorageSolutionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_d19af9c9-7c79-4769-8bca-a667174adddd" xlink:to="loc_mtrx_StorageSolutionsMember_80149c79-d06c-475f-9419-3ca0614baf8d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_IndustrialMember_292a083d-c5ea-4259-9d49-89138f712abd" xlink:href="mtrx-20200630.xsd#mtrx_IndustrialMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_d19af9c9-7c79-4769-8bca-a667174adddd" xlink:to="loc_mtrx_IndustrialMember_292a083d-c5ea-4259-9d49-89138f712abd" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_ReportingUnitMember_c16d48e5-96f4-4f74-a60d-f5a7c0831411" xlink:href="mtrx-20200630.xsd#mtrx_ReportingUnitMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_d19af9c9-7c79-4769-8bca-a667174adddd" xlink:to="loc_mtrx_ReportingUnitMember_c16d48e5-96f4-4f74-a60d-f5a7c0831411" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/GoodwillandOtherIntangibleAssetsDetailsTextual" xlink:type="simple" xlink:href="mtrx-20200630.xsd#GoodwillandOtherIntangibleAssetsDetailsTextual"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/GoodwillandOtherIntangibleAssetsDetailsTextual" xlink:type="extended" id="i55a9b2c94f3d47899edb443b3cb9b0ed_GoodwillandOtherIntangibleAssetsDetailsTextual">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_7278c3e3-e7f6-4a54-8dff-6576236f995c" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ImpairmentOfIntangibleAssetsFinitelived_2cc642ae-6803-4293-a2cc-ffcec9e23f26" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ImpairmentOfIntangibleAssetsFinitelived"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_7278c3e3-e7f6-4a54-8dff-6576236f995c" xlink:to="loc_us-gaap_ImpairmentOfIntangibleAssetsFinitelived_2cc642ae-6803-4293-a2cc-ffcec9e23f26" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsRemainingAmortizationPeriod1_2b637d60-b27c-45db-bd81-2b4195ba183c" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsRemainingAmortizationPeriod1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_7278c3e3-e7f6-4a54-8dff-6576236f995c" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsRemainingAmortizationPeriod1_2b637d60-b27c-45db-bd81-2b4195ba183c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsGross_d2636731-85d7-4ef1-994b-de91397396d7" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_7278c3e3-e7f6-4a54-8dff-6576236f995c" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsGross_d2636731-85d7-4ef1-994b-de91397396d7" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_8c4d0318-faa1-47d9-a769-622be5c039e6" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_7278c3e3-e7f6-4a54-8dff-6576236f995c" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_8c4d0318-faa1-47d9-a769-622be5c039e6" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_d2027238-ad29-4e6c-9042-68e87b319344" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_7278c3e3-e7f6-4a54-8dff-6576236f995c" xlink:to="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_d2027238-ad29-4e6c-9042-68e87b319344" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_78b4a443-8c8a-49c5-a9b0-8c512a7eacc3" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_d2027238-ad29-4e6c-9042-68e87b319344" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_78b4a443-8c8a-49c5-a9b0-8c512a7eacc3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_78b4a443-8c8a-49c5-a9b0-8c512a7eacc3_default" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_78b4a443-8c8a-49c5-a9b0-8c512a7eacc3" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_78b4a443-8c8a-49c5-a9b0-8c512a7eacc3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_e3f76751-9182-431a-89f9-926c050a0f5a" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_78b4a443-8c8a-49c5-a9b0-8c512a7eacc3" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_e3f76751-9182-431a-89f9-926c050a0f5a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_CustomerRelationshipImpairment1Member_6e820888-003c-43cb-bf1a-b2382e36253b" xlink:href="mtrx-20200630.xsd#mtrx_CustomerRelationshipImpairment1Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_e3f76751-9182-431a-89f9-926c050a0f5a" xlink:to="loc_mtrx_CustomerRelationshipImpairment1Member_6e820888-003c-43cb-bf1a-b2382e36253b" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_CustomerRelationshipImpairment2Member_328ac437-8cc8-40bb-90ed-f7d91d8e5f4e" xlink:href="mtrx-20200630.xsd#mtrx_CustomerRelationshipImpairment2Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_e3f76751-9182-431a-89f9-926c050a0f5a" xlink:to="loc_mtrx_CustomerRelationshipImpairment2Member_328ac437-8cc8-40bb-90ed-f7d91d8e5f4e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_CustomerRelationshipImpairment3Member_3d777488-5158-42f3-b27e-89c029b4c075" xlink:href="mtrx-20200630.xsd#mtrx_CustomerRelationshipImpairment3Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_e3f76751-9182-431a-89f9-926c050a0f5a" xlink:to="loc_mtrx_CustomerRelationshipImpairment3Member_3d777488-5158-42f3-b27e-89c029b4c075" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/GoodwillandOtherIntangibleAssetsDetails1" xlink:type="simple" xlink:href="mtrx-20200630.xsd#GoodwillandOtherIntangibleAssetsDetails1"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/GoodwillandOtherIntangibleAssetsDetails1" xlink:type="extended" id="i205be3796ffb41f98f35074ae99e515f_GoodwillandOtherIntangibleAssetsDetails1">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_bc9f24fc-d327-4104-ab2d-8d1d84524295" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedTradeNamesGross_2804e359-5b01-4856-a027-a4956075af42" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_FiniteLivedTradeNamesGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_bc9f24fc-d327-4104-ab2d-8d1d84524295" xlink:to="loc_us-gaap_FiniteLivedTradeNamesGross_2804e359-5b01-4856-a027-a4956075af42" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsFairValueDisclosure_0803ae47-6bf8-4f34-b1b6-a4d27f7c88a9" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsFairValueDisclosure"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_bc9f24fc-d327-4104-ab2d-8d1d84524295" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsFairValueDisclosure_0803ae47-6bf8-4f34-b1b6-a4d27f7c88a9" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IntangibleAssetsNetExcludingGoodwillAbstract_d31fab65-31d4-4c24-b6d2-715e17fc4184" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_IntangibleAssetsNetExcludingGoodwillAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_bc9f24fc-d327-4104-ab2d-8d1d84524295" xlink:to="loc_us-gaap_IntangibleAssetsNetExcludingGoodwillAbstract_d31fab65-31d4-4c24-b6d2-715e17fc4184" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetUsefulLife_2758a199-9528-4d54-a912-c0f86b523d4f" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetUsefulLife"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IntangibleAssetsNetExcludingGoodwillAbstract_d31fab65-31d4-4c24-b6d2-715e17fc4184" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetUsefulLife_2758a199-9528-4d54-a912-c0f86b523d4f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsGross_9540c2b9-3a71-4241-969a-38f109fce91f" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsGross"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IntangibleAssetsNetExcludingGoodwillAbstract_d31fab65-31d4-4c24-b6d2-715e17fc4184" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsGross_9540c2b9-3a71-4241-969a-38f109fce91f" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_155d0615-6b22-44a2-b894-69af075c9b5a" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IntangibleAssetsNetExcludingGoodwillAbstract_d31fab65-31d4-4c24-b6d2-715e17fc4184" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsAccumulatedAmortization_155d0615-6b22-44a2-b894-69af075c9b5a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsNet_6045d03f-11b1-4034-abc6-bcb1a53ee7c7" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsNet"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IntangibleAssetsNetExcludingGoodwillAbstract_d31fab65-31d4-4c24-b6d2-715e17fc4184" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsNet_6045d03f-11b1-4034-abc6-bcb1a53ee7c7" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AmortizationOfIntangibleAssets_925dd1a3-d300-4fb2-a158-2ca4e5d79843" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_AmortizationOfIntangibleAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IntangibleAssetsNetExcludingGoodwillAbstract_d31fab65-31d4-4c24-b6d2-715e17fc4184" xlink:to="loc_us-gaap_AmortizationOfIntangibleAssets_925dd1a3-d300-4fb2-a158-2ca4e5d79843" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_7ffcbb58-03c8-4aa4-8919-6a0b3f68d37a" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsLineItems_bc9f24fc-d327-4104-ab2d-8d1d84524295" xlink:to="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_7ffcbb58-03c8-4aa4-8919-6a0b3f68d37a" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_bfc03065-9d84-481e-83f9-eae93686f543" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_7ffcbb58-03c8-4aa4-8919-6a0b3f68d37a" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_bfc03065-9d84-481e-83f9-eae93686f543" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_bfc03065-9d84-481e-83f9-eae93686f543_default" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_bfc03065-9d84-481e-83f9-eae93686f543" xlink:to="loc_us-gaap_SegmentDomain_bfc03065-9d84-481e-83f9-eae93686f543_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_2fa2670d-13ee-4d6a-b006-bf84cd31ba5a" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_bfc03065-9d84-481e-83f9-eae93686f543" xlink:to="loc_us-gaap_SegmentDomain_2fa2670d-13ee-4d6a-b006-bf84cd31ba5a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_ReportingUnitMember_c7ee16f7-81d1-4092-845a-6171446bda0d" xlink:href="mtrx-20200630.xsd#mtrx_ReportingUnitMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_2fa2670d-13ee-4d6a-b006-bf84cd31ba5a" xlink:to="loc_mtrx_ReportingUnitMember_c7ee16f7-81d1-4092-845a-6171446bda0d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAxis_89ed0a68-df35-4155-9764-1fc4e5b5c987" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_BusinessAcquisitionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_7ffcbb58-03c8-4aa4-8919-6a0b3f68d37a" xlink:to="loc_us-gaap_BusinessAcquisitionAxis_89ed0a68-df35-4155-9764-1fc4e5b5c987" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_89ed0a68-df35-4155-9764-1fc4e5b5c987_default" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_89ed0a68-df35-4155-9764-1fc4e5b5c987" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_89ed0a68-df35-4155-9764-1fc4e5b5c987_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessAcquisitionAcquireeDomain_6d924aa1-1e15-48a1-9f65-0733775f05e3" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_BusinessAcquisitionAcquireeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_BusinessAcquisitionAxis_89ed0a68-df35-4155-9764-1fc4e5b5c987" xlink:to="loc_us-gaap_BusinessAcquisitionAcquireeDomain_6d924aa1-1e15-48a1-9f65-0733775f05e3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_BaillieTankEquipmentLtd.Member_c1a84d7a-9136-47c6-9e1e-b82c7aaf2317" xlink:href="mtrx-20200630.xsd#mtrx_BaillieTankEquipmentLtd.Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_6d924aa1-1e15-48a1-9f65-0733775f05e3" xlink:to="loc_mtrx_BaillieTankEquipmentLtd.Member_c1a84d7a-9136-47c6-9e1e-b82c7aaf2317" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_HoustonInterestsLLCMember_c41f3ccc-3189-4e33-b86e-e3dba79a7808" xlink:href="mtrx-20200630.xsd#mtrx_HoustonInterestsLLCMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_BusinessAcquisitionAcquireeDomain_6d924aa1-1e15-48a1-9f65-0733775f05e3" xlink:to="loc_mtrx_HoustonInterestsLLCMember_c41f3ccc-3189-4e33-b86e-e3dba79a7808" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_c6ee6fcf-a871-4274-97c3-c2e8d726d1ba" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_7ffcbb58-03c8-4aa4-8919-6a0b3f68d37a" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_c6ee6fcf-a871-4274-97c3-c2e8d726d1ba" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_c6ee6fcf-a871-4274-97c3-c2e8d726d1ba_default" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_c6ee6fcf-a871-4274-97c3-c2e8d726d1ba" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_c6ee6fcf-a871-4274-97c3-c2e8d726d1ba_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_c988c9be-9f8e-48d5-9d84-8a9f2c370544" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsByMajorClassAxis_c6ee6fcf-a871-4274-97c3-c2e8d726d1ba" xlink:to="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_c988c9be-9f8e-48d5-9d84-8a9f2c370544" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_SMElectricTradeNameMember_d34223c8-9810-460b-bc42-84aa106f5117" xlink:href="mtrx-20200630.xsd#mtrx_SMElectricTradeNameMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_c988c9be-9f8e-48d5-9d84-8a9f2c370544" xlink:to="loc_mtrx_SMElectricTradeNameMember_d34223c8-9810-460b-bc42-84aa106f5117" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IntellectualPropertyMember_50bec7c1-1144-4e2a-87bb-329cc8a957dc" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_IntellectualPropertyMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_c988c9be-9f8e-48d5-9d84-8a9f2c370544" xlink:to="loc_us-gaap_IntellectualPropertyMember_50bec7c1-1144-4e2a-87bb-329cc8a957dc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_CustomerBasedMember_c42abd49-09fa-489b-94fb-b63cecb0d460" xlink:href="mtrx-20200630.xsd#mtrx_CustomerBasedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_c988c9be-9f8e-48d5-9d84-8a9f2c370544" xlink:to="loc_mtrx_CustomerBasedMember_c42abd49-09fa-489b-94fb-b63cecb0d460" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoncompeteAgreementsMember_7781b9cb-6975-4e4b-8df9-961fbb07c2c7" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_NoncompeteAgreementsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_c988c9be-9f8e-48d5-9d84-8a9f2c370544" xlink:to="loc_us-gaap_NoncompeteAgreementsMember_7781b9cb-6975-4e4b-8df9-961fbb07c2c7" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TradeNamesMember_1ebcd77d-9e2e-44fd-9338-40a4bfd1fc8a" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_TradeNamesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_FiniteLivedIntangibleAssetsMajorClassNameDomain_c988c9be-9f8e-48d5-9d84-8a9f2c370544" xlink:to="loc_us-gaap_TradeNamesMember_1ebcd77d-9e2e-44fd-9338-40a4bfd1fc8a" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis_0867be7d-6539-42a9-a82d-768f38ceba80" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_7ffcbb58-03c8-4aa4-8919-6a0b3f68d37a" xlink:to="loc_us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis_0867be7d-6539-42a9-a82d-768f38ceba80" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain_0867be7d-6539-42a9-a82d-768f38ceba80_default" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis_0867be7d-6539-42a9-a82d-768f38ceba80" xlink:to="loc_us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain_0867be7d-6539-42a9-a82d-768f38ceba80_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain_bec0a551-64f4-4c54-8ea3-417cdd50e896" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IndefiniteLivedIntangibleAssetsByMajorClassAxis_0867be7d-6539-42a9-a82d-768f38ceba80" xlink:to="loc_us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain_bec0a551-64f4-4c54-8ea3-417cdd50e896" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TradeNamesMember_78a81394-deb2-490e-8a8e-4f663d5fdbf5" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_TradeNamesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IndefiniteLivedIntangibleAssetsMajorClassNameDomain_bec0a551-64f4-4c54-8ea3-417cdd50e896" xlink:to="loc_us-gaap_TradeNamesMember_78a81394-deb2-490e-8a8e-4f663d5fdbf5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_18925de1-6d97-4735-8455-7f9a69a8eba3" xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfFiniteLivedIntangibleAssetsTable_7ffcbb58-03c8-4aa4-8919-6a0b3f68d37a" xlink:to="loc_srt_RangeAxis_18925de1-6d97-4735-8455-7f9a69a8eba3" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_18925de1-6d97-4735-8455-7f9a69a8eba3_default" xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_18925de1-6d97-4735-8455-7f9a69a8eba3" xlink:to="loc_srt_RangeMember_18925de1-6d97-4735-8455-7f9a69a8eba3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_3b14e30c-b31d-4d69-bfd0-c1222a009e8a" xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_18925de1-6d97-4735-8455-7f9a69a8eba3" xlink:to="loc_srt_RangeMember_3b14e30c-b31d-4d69-bfd0-c1222a009e8a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_9e12bbb0-ac1a-4d5a-afa8-fb17a682e0be" xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_3b14e30c-b31d-4d69-bfd0-c1222a009e8a" xlink:to="loc_srt_MinimumMember_9e12bbb0-ac1a-4d5a-afa8-fb17a682e0be" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_bdcd3715-fe72-4f39-8bc6-115f05cb09d0" xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_3b14e30c-b31d-4d69-bfd0-c1222a009e8a" xlink:to="loc_srt_MaximumMember_bdcd3715-fe72-4f39-8bc6-115f05cb09d0" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/Debt" xlink:type="simple" xlink:href="mtrx-20200630.xsd#Debt"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/Debt" xlink:type="extended" id="i98f2933da4e14ee0936e6438590446dc_Debt"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/DebtTables" xlink:type="simple" xlink:href="mtrx-20200630.xsd#DebtTables"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/DebtTables" xlink:type="extended" id="i3d5318e64acd43f98edb8b0920940965_DebtTables"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/DebtDetailsTextual" xlink:type="simple" xlink:href="mtrx-20200630.xsd#DebtDetailsTextual"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/DebtDetailsTextual" xlink:type="extended" id="i282b255efac04250b8838d98a3058cbf_DebtDetailsTextual">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityLineItems_3acdcc66-45d7-4f9d-83ae-005b19d43685" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_LineOfCreditFacilityLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_DebtTextualAbstract_4afad1c2-1987-4dc9-9d3f-67b81b773edd" xlink:href="mtrx-20200630.xsd#mtrx_DebtTextualAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_3acdcc66-45d7-4f9d-83ae-005b19d43685" xlink:to="loc_mtrx_DebtTextualAbstract_4afad1c2-1987-4dc9-9d3f-67b81b773edd" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_c81cb7f1-0151-4431-aedf-16ad83c379a1" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtrx_DebtTextualAbstract_4afad1c2-1987-4dc9-9d3f-67b81b773edd" xlink:to="loc_us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity_c81cb7f1-0151-4431-aedf-16ad83c379a1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityExpirationDate1_05e1756e-a468-4295-a113-eb134f24ab0c" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_LineOfCreditFacilityExpirationDate1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtrx_DebtTextualAbstract_4afad1c2-1987-4dc9-9d3f-67b81b773edd" xlink:to="loc_us-gaap_LineOfCreditFacilityExpirationDate1_05e1756e-a468-4295-a113-eb134f24ab0c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_SublimitonAustralianDollarCanadianDollarEuroandPoundsSterling_5df2f3d4-3bf9-4b88-97f6-498162d6a6b6" xlink:href="mtrx-20200630.xsd#mtrx_SublimitonAustralianDollarCanadianDollarEuroandPoundsSterling"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtrx_DebtTextualAbstract_4afad1c2-1987-4dc9-9d3f-67b81b773edd" xlink:to="loc_mtrx_SublimitonAustralianDollarCanadianDollarEuroandPoundsSterling_5df2f3d4-3bf9-4b88-97f6-498162d6a6b6" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_Sublimitonlettersofcreditunderthecreditfacility_6b4c7bf4-1398-4488-94d4-fbbd84569582" xlink:href="mtrx-20200630.xsd#mtrx_Sublimitonlettersofcreditunderthecreditfacility"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtrx_DebtTextualAbstract_4afad1c2-1987-4dc9-9d3f-67b81b773edd" xlink:to="loc_mtrx_Sublimitonlettersofcreditunderthecreditfacility_6b4c7bf4-1398-4488-94d4-fbbd84569582" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_LineOfCreditBasisSpreadOnAlternateBaseRateMinimum_aad17772-8061-4026-b330-27b97d870428" xlink:href="mtrx-20200630.xsd#mtrx_LineOfCreditBasisSpreadOnAlternateBaseRateMinimum"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtrx_DebtTextualAbstract_4afad1c2-1987-4dc9-9d3f-67b81b773edd" xlink:to="loc_mtrx_LineOfCreditBasisSpreadOnAlternateBaseRateMinimum_aad17772-8061-4026-b330-27b97d870428" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_LineOfCreditBasisSpreadOnAlternateBaseRateMaximum_23bf0353-5815-4da2-9658-edd0da65716a" xlink:href="mtrx-20200630.xsd#mtrx_LineOfCreditBasisSpreadOnAlternateBaseRateMaximum"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtrx_DebtTextualAbstract_4afad1c2-1987-4dc9-9d3f-67b81b773edd" xlink:to="loc_mtrx_LineOfCreditBasisSpreadOnAlternateBaseRateMaximum_23bf0353-5815-4da2-9658-edd0da65716a" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_LineOfCreditBasisSpreadOnAdjustedLIBOEURIBOandCDORMinimum_d0edc088-7c16-4d3b-9235-10bae2dbd0f4" xlink:href="mtrx-20200630.xsd#mtrx_LineOfCreditBasisSpreadOnAdjustedLIBOEURIBOandCDORMinimum"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtrx_DebtTextualAbstract_4afad1c2-1987-4dc9-9d3f-67b81b773edd" xlink:to="loc_mtrx_LineOfCreditBasisSpreadOnAdjustedLIBOEURIBOandCDORMinimum_d0edc088-7c16-4d3b-9235-10bae2dbd0f4" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_LineOfCreditBasisSpreadOnAdjustedLIBOEURIBOandCDORMaximum_ca65c991-13de-4900-9f80-a81e26a04fd9" xlink:href="mtrx-20200630.xsd#mtrx_LineOfCreditBasisSpreadOnAdjustedLIBOEURIBOandCDORMaximum"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtrx_DebtTextualAbstract_4afad1c2-1987-4dc9-9d3f-67b81b773edd" xlink:to="loc_mtrx_LineOfCreditBasisSpreadOnAdjustedLIBOEURIBOandCDORMaximum_ca65c991-13de-4900-9f80-a81e26a04fd9" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_LineOfCreditBasisSpreadOnCanadianPrimeRateMinimum_0e7607a3-17d4-404d-8ba7-70a1493c88ca" xlink:href="mtrx-20200630.xsd#mtrx_LineOfCreditBasisSpreadOnCanadianPrimeRateMinimum"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtrx_DebtTextualAbstract_4afad1c2-1987-4dc9-9d3f-67b81b773edd" xlink:to="loc_mtrx_LineOfCreditBasisSpreadOnCanadianPrimeRateMinimum_0e7607a3-17d4-404d-8ba7-70a1493c88ca" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_LineOfCreditBasisSpreadOnCanadianPrimeRateMaximum_43f878be-59a2-4ae3-ba92-5f5a021721e0" xlink:href="mtrx-20200630.xsd#mtrx_LineOfCreditBasisSpreadOnCanadianPrimeRateMaximum"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtrx_DebtTextualAbstract_4afad1c2-1987-4dc9-9d3f-67b81b773edd" xlink:to="loc_mtrx_LineOfCreditBasisSpreadOnCanadianPrimeRateMaximum_43f878be-59a2-4ae3-ba92-5f5a021721e0" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage_ab0151dc-03d8-4689-a878-971cbe4b6ef7" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtrx_DebtTextualAbstract_4afad1c2-1987-4dc9-9d3f-67b81b773edd" xlink:to="loc_us-gaap_LineOfCreditFacilityUnusedCapacityCommitmentFeePercentage_ab0151dc-03d8-4689-a878-971cbe4b6ef7" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_SeniorLeverageRatioMaximum_720badbb-6c13-4dc1-ba43-d2bdf2697697" xlink:href="mtrx-20200630.xsd#mtrx_SeniorLeverageRatioMaximum"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtrx_DebtTextualAbstract_4afad1c2-1987-4dc9-9d3f-67b81b773edd" xlink:to="loc_mtrx_SeniorLeverageRatioMaximum_720badbb-6c13-4dc1-ba43-d2bdf2697697" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_SeniorLeverageRatioMinimum_663a64b8-0fc0-4f9e-b5a5-84c450d8c8b7" xlink:href="mtrx-20200630.xsd#mtrx_SeniorLeverageRatioMinimum"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtrx_DebtTextualAbstract_4afad1c2-1987-4dc9-9d3f-67b81b773edd" xlink:to="loc_mtrx_SeniorLeverageRatioMinimum_663a64b8-0fc0-4f9e-b5a5-84c450d8c8b7" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_FixedChargeCoverageRatioMaximum_a2a2569e-13a3-495e-9089-21059b3af9d4" xlink:href="mtrx-20200630.xsd#mtrx_FixedChargeCoverageRatioMaximum"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtrx_DebtTextualAbstract_4afad1c2-1987-4dc9-9d3f-67b81b773edd" xlink:to="loc_mtrx_FixedChargeCoverageRatioMaximum_a2a2569e-13a3-495e-9089-21059b3af9d4" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_FixedChargeCoverageRatioMinimum_31284410-0c7e-43ae-9788-593ad2db852f" xlink:href="mtrx-20200630.xsd#mtrx_FixedChargeCoverageRatioMinimum"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtrx_DebtTextualAbstract_4afad1c2-1987-4dc9-9d3f-67b81b773edd" xlink:to="loc_mtrx_FixedChargeCoverageRatioMinimum_31284410-0c7e-43ae-9788-593ad2db852f" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_AmountOfLimitOnAssetDispositions_5a36e6bb-8a8e-4ad0-a421-a47d26651362" xlink:href="mtrx-20200630.xsd#mtrx_AmountOfLimitOnAssetDispositions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtrx_DebtTextualAbstract_4afad1c2-1987-4dc9-9d3f-67b81b773edd" xlink:to="loc_mtrx_AmountOfLimitOnAssetDispositions_5a36e6bb-8a8e-4ad0-a421-a47d26651362" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAcquiredIndefiniteLivedIntangibleAssetsByMajorClassTable_33031e58-0944-45cd-a2d4-4df6180fa27e" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ScheduleOfAcquiredIndefiniteLivedIntangibleAssetsByMajorClassTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_LineOfCreditFacilityLineItems_3acdcc66-45d7-4f9d-83ae-005b19d43685" xlink:to="loc_us-gaap_ScheduleOfAcquiredIndefiniteLivedIntangibleAssetsByMajorClassTable_33031e58-0944-45cd-a2d4-4df6180fa27e" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableRateAxis_dd4693bf-3294-453e-a0db-eb057ac193b3" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_VariableRateAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAcquiredIndefiniteLivedIntangibleAssetsByMajorClassTable_33031e58-0944-45cd-a2d4-4df6180fa27e" xlink:to="loc_us-gaap_VariableRateAxis_dd4693bf-3294-453e-a0db-eb057ac193b3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableRateDomain_dd4693bf-3294-453e-a0db-eb057ac193b3_default" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_VariableRateDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_VariableRateAxis_dd4693bf-3294-453e-a0db-eb057ac193b3" xlink:to="loc_us-gaap_VariableRateDomain_dd4693bf-3294-453e-a0db-eb057ac193b3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_VariableRateDomain_7c3afcb0-e81c-42f0-bfd0-aeeb176c162d" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_VariableRateDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_VariableRateAxis_dd4693bf-3294-453e-a0db-eb057ac193b3" xlink:to="loc_us-gaap_VariableRateDomain_7c3afcb0-e81c-42f0-bfd0-aeeb176c162d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_CdorRateMember_9278fdd2-cbfb-4ae3-954c-4ab30f52e792" xlink:href="mtrx-20200630.xsd#mtrx_CdorRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableRateDomain_7c3afcb0-e81c-42f0-bfd0-aeeb176c162d" xlink:to="loc_mtrx_CdorRateMember_9278fdd2-cbfb-4ae3-954c-4ab30f52e792" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_CanadianPrimeRateMember_f9aef7f2-6f8c-4d11-aa10-97bb5da4efd0" xlink:href="mtrx-20200630.xsd#mtrx_CanadianPrimeRateMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_VariableRateDomain_7c3afcb0-e81c-42f0-bfd0-aeeb176c162d" xlink:to="loc_mtrx_CanadianPrimeRateMember_f9aef7f2-6f8c-4d11-aa10-97bb5da4efd0" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_48c430b8-872a-454d-9384-02c8b685f808" xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAcquiredIndefiniteLivedIntangibleAssetsByMajorClassTable_33031e58-0944-45cd-a2d4-4df6180fa27e" xlink:to="loc_srt_RangeAxis_48c430b8-872a-454d-9384-02c8b685f808" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_48c430b8-872a-454d-9384-02c8b685f808_default" xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_48c430b8-872a-454d-9384-02c8b685f808" xlink:to="loc_srt_RangeMember_48c430b8-872a-454d-9384-02c8b685f808_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_6fc269f6-304b-4cf5-a91a-318ced35947a" xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_48c430b8-872a-454d-9384-02c8b685f808" xlink:to="loc_srt_RangeMember_6fc269f6-304b-4cf5-a91a-318ced35947a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_c7bf9c71-c290-48b5-ba56-a19f31136018" xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_6fc269f6-304b-4cf5-a91a-318ced35947a" xlink:to="loc_srt_MinimumMember_c7bf9c71-c290-48b5-ba56-a19f31136018" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_78cd76be-8e16-483d-92ec-af5196df2a60" xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_6fc269f6-304b-4cf5-a91a-318ced35947a" xlink:to="loc_srt_MaximumMember_78cd76be-8e16-483d-92ec-af5196df2a60" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/DebtDetails" xlink:type="simple" xlink:href="mtrx-20200630.xsd#DebtDetails"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/DebtDetails" xlink:type="extended" id="ia2d90fc399874c67a744343f9414bfd0_DebtDetails"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/IncomeTaxes" xlink:type="simple" xlink:href="mtrx-20200630.xsd#IncomeTaxes"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/IncomeTaxes" xlink:type="extended" id="ie88ac51d088048c8bf2010f3c39f5036_IncomeTaxes"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/IncomeTaxesTables" xlink:type="simple" xlink:href="mtrx-20200630.xsd#IncomeTaxesTables"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/IncomeTaxesTables" xlink:type="extended" id="i0ea83f3c1899429bae69a6345e509d16_IncomeTaxesTables"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/IncomeTaxesDetailsTextual" xlink:type="simple" xlink:href="mtrx-20200630.xsd#IncomeTaxesDetailsTextual"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/IncomeTaxesDetailsTextual" xlink:type="extended" id="if163d6d9072c4c13b1a1f6f76711d444_IncomeTaxesDetailsTextual"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/IncomeTaxesDetails" xlink:type="simple" xlink:href="mtrx-20200630.xsd#IncomeTaxesDetails"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/IncomeTaxesDetails" xlink:type="extended" id="ifcb74fa67b924a0dafd54c73d512990d_IncomeTaxesDetails"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/IncomeTaxesDetails1" xlink:type="simple" xlink:href="mtrx-20200630.xsd#IncomeTaxesDetails1"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/IncomeTaxesDetails1" xlink:type="extended" id="i41c0e77885cf4dbbbd2b2b5f1ff98b33_IncomeTaxesDetails1"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/IncomeTaxesDetails2" xlink:type="simple" xlink:href="mtrx-20200630.xsd#IncomeTaxesDetails2"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/IncomeTaxesDetails2" xlink:type="extended" id="ic1a985be49a44e208aec1ee94de796ff_IncomeTaxesDetails2"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/IncomeTaxesDetails3" xlink:type="simple" xlink:href="mtrx-20200630.xsd#IncomeTaxesDetails3"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/IncomeTaxesDetails3" xlink:type="extended" id="ib20fd3711cb4402c8b5e923e2111734b_IncomeTaxesDetails3"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/IncomeTaxesDetails4" xlink:type="simple" xlink:href="mtrx-20200630.xsd#IncomeTaxesDetails4"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/IncomeTaxesDetails4" xlink:type="extended" id="i6c3579ec1e8945eab3ae9bc05e896219_IncomeTaxesDetails4"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/IncomeTaxesDetails5" xlink:type="simple" xlink:href="mtrx-20200630.xsd#IncomeTaxesDetails5"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/IncomeTaxesDetails5" xlink:type="extended" id="i44dd56704c3d47ddaf1bd6f3ee77b3c9_IncomeTaxesDetails5">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLossCarryforwardsLineItems_e54408e3-8aca-4cb1-9eca-19a11d3bbfd4" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_OperatingLossCarryforwardsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLossCarryforwardsLimitationsOnUse_0077dd03-d8e1-4eab-8484-ae3d13e6a564" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_OperatingLossCarryforwardsLimitationsOnUse"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OperatingLossCarryforwardsLineItems_e54408e3-8aca-4cb1-9eca-19a11d3bbfd4" xlink:to="loc_us-gaap_OperatingLossCarryforwardsLimitationsOnUse_0077dd03-d8e1-4eab-8484-ae3d13e6a564" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLossCarryforwards_259c358d-a81c-4038-98e6-42e6a7287cf3" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_OperatingLossCarryforwards"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_OperatingLossCarryforwardsLineItems_e54408e3-8aca-4cb1-9eca-19a11d3bbfd4" xlink:to="loc_us-gaap_OperatingLossCarryforwards_259c358d-a81c-4038-98e6-42e6a7287cf3" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingLossCarryforwardsTable_04ed2455-f933-4129-9380-daccddbd68b2" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_OperatingLossCarryforwardsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_OperatingLossCarryforwardsLineItems_e54408e3-8aca-4cb1-9eca-19a11d3bbfd4" xlink:to="loc_us-gaap_OperatingLossCarryforwardsTable_04ed2455-f933-4129-9380-daccddbd68b2" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxAuthorityAxis_f851912f-bbf2-4058-9731-88b6ab1b3d67" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_IncomeTaxAuthorityAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_OperatingLossCarryforwardsTable_04ed2455-f933-4129-9380-daccddbd68b2" xlink:to="loc_us-gaap_IncomeTaxAuthorityAxis_f851912f-bbf2-4058-9731-88b6ab1b3d67" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxAuthorityDomain_f851912f-bbf2-4058-9731-88b6ab1b3d67_default" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_IncomeTaxAuthorityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeTaxAuthorityAxis_f851912f-bbf2-4058-9731-88b6ab1b3d67" xlink:to="loc_us-gaap_IncomeTaxAuthorityDomain_f851912f-bbf2-4058-9731-88b6ab1b3d67_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxAuthorityDomain_6696a679-42c6-4fc3-9bab-ada0f6eaab2b" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_IncomeTaxAuthorityDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeTaxAuthorityAxis_f851912f-bbf2-4058-9731-88b6ab1b3d67" xlink:to="loc_us-gaap_IncomeTaxAuthorityDomain_6696a679-42c6-4fc3-9bab-ada0f6eaab2b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StateAndLocalJurisdictionMember_c16bc7a7-4403-49a9-9797-e4945aed917d" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_StateAndLocalJurisdictionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxAuthorityDomain_6696a679-42c6-4fc3-9bab-ada0f6eaab2b" xlink:to="loc_us-gaap_StateAndLocalJurisdictionMember_c16bc7a7-4403-49a9-9797-e4945aed917d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ForeignCountryMember_5be539af-0e31-44d0-85e1-c8a1289f60ff" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ForeignCountryMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_IncomeTaxAuthorityDomain_6696a679-42c6-4fc3-9bab-ada0f6eaab2b" xlink:to="loc_us-gaap_ForeignCountryMember_5be539af-0e31-44d0-85e1-c8a1289f60ff" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxAuthorityNameAxis_4dbd4570-03df-48c9-a057-85985e44144e" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_IncomeTaxAuthorityNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_OperatingLossCarryforwardsTable_04ed2455-f933-4129-9380-daccddbd68b2" xlink:to="loc_us-gaap_IncomeTaxAuthorityNameAxis_4dbd4570-03df-48c9-a057-85985e44144e" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxAuthorityNameDomain_4dbd4570-03df-48c9-a057-85985e44144e_default" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_IncomeTaxAuthorityNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeTaxAuthorityNameAxis_4dbd4570-03df-48c9-a057-85985e44144e" xlink:to="loc_us-gaap_IncomeTaxAuthorityNameDomain_4dbd4570-03df-48c9-a057-85985e44144e_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxAuthorityNameDomain_9a4112ea-dc33-468a-bdf1-291ac8d2c9d5" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_IncomeTaxAuthorityNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeTaxAuthorityNameAxis_4dbd4570-03df-48c9-a057-85985e44144e" xlink:to="loc_us-gaap_IncomeTaxAuthorityNameDomain_9a4112ea-dc33-468a-bdf1-291ac8d2c9d5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TaxPeriodAxis_da2f541f-a33b-4e20-bae7-61458ea3136d" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_TaxPeriodAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_OperatingLossCarryforwardsTable_04ed2455-f933-4129-9380-daccddbd68b2" xlink:to="loc_us-gaap_TaxPeriodAxis_da2f541f-a33b-4e20-bae7-61458ea3136d" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TaxPeriodDomain_da2f541f-a33b-4e20-bae7-61458ea3136d_default" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_TaxPeriodDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_TaxPeriodAxis_da2f541f-a33b-4e20-bae7-61458ea3136d" xlink:to="loc_us-gaap_TaxPeriodDomain_da2f541f-a33b-4e20-bae7-61458ea3136d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TaxPeriodDomain_95f9e04e-56ac-4eeb-b4c2-43a1d10dd683" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_TaxPeriodDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_TaxPeriodAxis_da2f541f-a33b-4e20-bae7-61458ea3136d" xlink:to="loc_us-gaap_TaxPeriodDomain_95f9e04e-56ac-4eeb-b4c2-43a1d10dd683" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/IncomeTaxesDetails6" xlink:type="simple" xlink:href="mtrx-20200630.xsd#IncomeTaxesDetails6"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/IncomeTaxesDetails6" xlink:type="extended" id="ifa9f4d58c9434571886981fd076794d2_IncomeTaxesDetails6">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TaxCreditCarryforwardLineItems_8a99e5f0-bb1a-4804-acbc-fe8fa6579b76" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_TaxCreditCarryforwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TaxCreditCarryforwardDescription_517fb3b0-75f7-4ac6-b583-7bfd1b10448d" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_TaxCreditCarryforwardDescription"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TaxCreditCarryforwardLineItems_8a99e5f0-bb1a-4804-acbc-fe8fa6579b76" xlink:to="loc_us-gaap_TaxCreditCarryforwardDescription_517fb3b0-75f7-4ac6-b583-7bfd1b10448d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TaxCreditCarryforwardAmount_544c1a10-a4fa-482c-ba5b-cc0135b7543a" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_TaxCreditCarryforwardAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_TaxCreditCarryforwardLineItems_8a99e5f0-bb1a-4804-acbc-fe8fa6579b76" xlink:to="loc_us-gaap_TaxCreditCarryforwardAmount_544c1a10-a4fa-482c-ba5b-cc0135b7543a" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TaxCreditCarryforwardTable_416aa735-062d-4e67-a36f-d2582cea3b92" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_TaxCreditCarryforwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_TaxCreditCarryforwardLineItems_8a99e5f0-bb1a-4804-acbc-fe8fa6579b76" xlink:to="loc_us-gaap_TaxCreditCarryforwardTable_416aa735-062d-4e67-a36f-d2582cea3b92" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_IncomeTaxAuthorityDescriptionAxis_c7f32450-fa80-4342-913a-96bdd81638fc" xlink:href="mtrx-20200630.xsd#mtrx_IncomeTaxAuthorityDescriptionAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_TaxCreditCarryforwardTable_416aa735-062d-4e67-a36f-d2582cea3b92" xlink:to="loc_mtrx_IncomeTaxAuthorityDescriptionAxis_c7f32450-fa80-4342-913a-96bdd81638fc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_IncomeTaxAuthorityDescriptionDomain_c7f32450-fa80-4342-913a-96bdd81638fc_default" xlink:href="mtrx-20200630.xsd#mtrx_IncomeTaxAuthorityDescriptionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_mtrx_IncomeTaxAuthorityDescriptionAxis_c7f32450-fa80-4342-913a-96bdd81638fc" xlink:to="loc_mtrx_IncomeTaxAuthorityDescriptionDomain_c7f32450-fa80-4342-913a-96bdd81638fc_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_IncomeTaxAuthorityDescriptionDomain_f7c63628-257c-43ef-bac5-cedc151af00e" xlink:href="mtrx-20200630.xsd#mtrx_IncomeTaxAuthorityDescriptionDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_mtrx_IncomeTaxAuthorityDescriptionAxis_c7f32450-fa80-4342-913a-96bdd81638fc" xlink:to="loc_mtrx_IncomeTaxAuthorityDescriptionDomain_f7c63628-257c-43ef-bac5-cedc151af00e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_StatetaxcreditMember_00eaf21e-41c6-4021-a522-6d8638ff0b9c" xlink:href="mtrx-20200630.xsd#mtrx_StatetaxcreditMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtrx_IncomeTaxAuthorityDescriptionDomain_f7c63628-257c-43ef-bac5-cedc151af00e" xlink:to="loc_mtrx_StatetaxcreditMember_00eaf21e-41c6-4021-a522-6d8638ff0b9c" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_FederaltaxcreditcarryforwardMember_68813331-f536-4099-bf24-ac04b3fb7f11" xlink:href="mtrx-20200630.xsd#mtrx_FederaltaxcreditcarryforwardMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtrx_IncomeTaxAuthorityDescriptionDomain_f7c63628-257c-43ef-bac5-cedc151af00e" xlink:to="loc_mtrx_FederaltaxcreditcarryforwardMember_68813331-f536-4099-bf24-ac04b3fb7f11" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_ForeigntaxcreditcarryforwardMember_86d34f0a-7d02-49a9-9014-9552229d769b" xlink:href="mtrx-20200630.xsd#mtrx_ForeigntaxcreditcarryforwardMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtrx_IncomeTaxAuthorityDescriptionDomain_f7c63628-257c-43ef-bac5-cedc151af00e" xlink:to="loc_mtrx_ForeigntaxcreditcarryforwardMember_86d34f0a-7d02-49a9-9014-9552229d769b" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TaxCreditCarryforwardAxis_6c2c2cd5-9704-4f8e-bb6f-1171c7940c62" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_TaxCreditCarryforwardAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_TaxCreditCarryforwardTable_416aa735-062d-4e67-a36f-d2582cea3b92" xlink:to="loc_us-gaap_TaxCreditCarryforwardAxis_6c2c2cd5-9704-4f8e-bb6f-1171c7940c62" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TaxCreditCarryforwardNameDomain_6c2c2cd5-9704-4f8e-bb6f-1171c7940c62_default" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_TaxCreditCarryforwardNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_TaxCreditCarryforwardAxis_6c2c2cd5-9704-4f8e-bb6f-1171c7940c62" xlink:to="loc_us-gaap_TaxCreditCarryforwardNameDomain_6c2c2cd5-9704-4f8e-bb6f-1171c7940c62_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TaxCreditCarryforwardNameDomain_6b4f4570-4763-49d2-89d7-da080ec32732" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_TaxCreditCarryforwardNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_TaxCreditCarryforwardAxis_6c2c2cd5-9704-4f8e-bb6f-1171c7940c62" xlink:to="loc_us-gaap_TaxCreditCarryforwardNameDomain_6b4f4570-4763-49d2-89d7-da080ec32732" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxAuthorityNameAxis_02450f85-ea87-4348-bf00-d2de45d74e0b" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_IncomeTaxAuthorityNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_TaxCreditCarryforwardTable_416aa735-062d-4e67-a36f-d2582cea3b92" xlink:to="loc_us-gaap_IncomeTaxAuthorityNameAxis_02450f85-ea87-4348-bf00-d2de45d74e0b" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxAuthorityNameDomain_02450f85-ea87-4348-bf00-d2de45d74e0b_default" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_IncomeTaxAuthorityNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_IncomeTaxAuthorityNameAxis_02450f85-ea87-4348-bf00-d2de45d74e0b" xlink:to="loc_us-gaap_IncomeTaxAuthorityNameDomain_02450f85-ea87-4348-bf00-d2de45d74e0b_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IncomeTaxAuthorityNameDomain_963b368d-515b-4165-b8de-56aa34f4107f" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_IncomeTaxAuthorityNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_IncomeTaxAuthorityNameAxis_02450f85-ea87-4348-bf00-d2de45d74e0b" xlink:to="loc_us-gaap_IncomeTaxAuthorityNameDomain_963b368d-515b-4165-b8de-56aa34f4107f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TaxPeriodAxis_20667a8c-3855-430b-b0c7-b365827d1ebf" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_TaxPeriodAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_TaxCreditCarryforwardTable_416aa735-062d-4e67-a36f-d2582cea3b92" xlink:to="loc_us-gaap_TaxPeriodAxis_20667a8c-3855-430b-b0c7-b365827d1ebf" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TaxPeriodDomain_20667a8c-3855-430b-b0c7-b365827d1ebf_default" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_TaxPeriodDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_TaxPeriodAxis_20667a8c-3855-430b-b0c7-b365827d1ebf" xlink:to="loc_us-gaap_TaxPeriodDomain_20667a8c-3855-430b-b0c7-b365827d1ebf_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_TaxPeriodDomain_aca7132e-a80f-46d6-abe9-a94e798894d7" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_TaxPeriodDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_TaxPeriodAxis_20667a8c-3855-430b-b0c7-b365827d1ebf" xlink:to="loc_us-gaap_TaxPeriodDomain_aca7132e-a80f-46d6-abe9-a94e798894d7" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/CommitmentsandContingencies" xlink:type="simple" xlink:href="mtrx-20200630.xsd#CommitmentsandContingencies"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/CommitmentsandContingencies" xlink:type="extended" id="i3f555af43a7948128c722352e17db491_CommitmentsandContingencies"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/CommitmentsandContingenciesDetailsTextual" xlink:type="simple" xlink:href="mtrx-20200630.xsd#CommitmentsandContingenciesDetailsTextual"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/CommitmentsandContingenciesDetailsTextual" xlink:type="extended" id="iaa732d292e1e450c953ca9c99aa98bb8_CommitmentsandContingenciesDetailsTextual"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/Leases" xlink:type="simple" xlink:href="mtrx-20200630.xsd#Leases"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/Leases" xlink:type="extended" id="i090d6f4a90d94767bc6fd4800b720ae8_Leases"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/LeasesTables" xlink:type="simple" xlink:href="mtrx-20200630.xsd#LeasesTables"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/LeasesTables" xlink:type="extended" id="i6a6d9e961bcd44b5b783c98ad59da0e3_LeasesTables"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/LeasesNarrativeDetails" xlink:type="simple" xlink:href="mtrx-20200630.xsd#LeasesNarrativeDetails"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/LeasesNarrativeDetails" xlink:type="extended" id="i84b5a31f29f84880b01d5bdc408345f5_LeasesNarrativeDetails"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/LeasesComponentsofLeaseCostsDetails" xlink:type="simple" xlink:href="mtrx-20200630.xsd#LeasesComponentsofLeaseCostsDetails"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/LeasesComponentsofLeaseCostsDetails" xlink:type="extended" id="i71cf5ea8ff8747bc951683379bf6bea0_LeasesComponentsofLeaseCostsDetails"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/LeasesMaturityAnalysisDetails" xlink:type="simple" xlink:href="mtrx-20200630.xsd#LeasesMaturityAnalysisDetails"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/LeasesMaturityAnalysisDetails" xlink:type="extended" id="i3a1582300ff342e3bc82f8c7eaeaa933_LeasesMaturityAnalysisDetails"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/LeasesOtherLeaseInformationDetails" xlink:type="simple" xlink:href="mtrx-20200630.xsd#LeasesOtherLeaseInformationDetails"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/LeasesOtherLeaseInformationDetails" xlink:type="extended" id="ie002796be1834db8afe871c1f20ec96a_LeasesOtherLeaseInformationDetails"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/LeasesSupplementalCashFlowDisclosuresDetails" xlink:type="simple" xlink:href="mtrx-20200630.xsd#LeasesSupplementalCashFlowDisclosuresDetails"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/LeasesSupplementalCashFlowDisclosuresDetails" xlink:type="extended" id="idf086588f27b4681bb754e47e0025402_LeasesSupplementalCashFlowDisclosuresDetails"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/StockholdersEquity" xlink:type="simple" xlink:href="mtrx-20200630.xsd#StockholdersEquity"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/StockholdersEquity" xlink:type="extended" id="i3ebdbdd6c7b24d0196cd927ce4d89078_StockholdersEquity"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/StockholdersEquityDetailsTextual" xlink:type="simple" xlink:href="mtrx-20200630.xsd#StockholdersEquityDetailsTextual"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/StockholdersEquityDetailsTextual" xlink:type="extended" id="i8efe6cc50b3e41c89b5680966c926ec5_StockholdersEquityDetailsTextual">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityClassOfTreasuryStockLineItems_423d3581-894d-48dc-a09d-9692d1d48270" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_EquityClassOfTreasuryStockLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockRepurchaseProgramExpirationDate_34a2ecbb-b43f-4448-8ef3-225ca797f20e" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_StockRepurchaseProgramExpirationDate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityClassOfTreasuryStockLineItems_423d3581-894d-48dc-a09d-9692d1d48270" xlink:to="loc_us-gaap_StockRepurchaseProgramExpirationDate_34a2ecbb-b43f-4448-8ef3-225ca797f20e" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PreferredStockSharesAuthorized_4c6ceb43-b3b4-4dd8-8b75-989c090a035f" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_PreferredStockSharesAuthorized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityClassOfTreasuryStockLineItems_423d3581-894d-48dc-a09d-9692d1d48270" xlink:to="loc_us-gaap_PreferredStockSharesAuthorized_4c6ceb43-b3b4-4dd8-8b75-989c090a035f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StockRepurchaseProgramAuthorizedAmount1_3205e6a8-025c-440c-b693-551dab231505" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_StockRepurchaseProgramAuthorizedAmount1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityClassOfTreasuryStockLineItems_423d3581-894d-48dc-a09d-9692d1d48270" xlink:to="loc_us-gaap_StockRepurchaseProgramAuthorizedAmount1_3205e6a8-025c-440c-b693-551dab231505" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfTreasuryStockTable_425692ea-9217-494c-bd5d-af0f2cb570b5" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ClassOfTreasuryStockTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_EquityClassOfTreasuryStockLineItems_423d3581-894d-48dc-a09d-9692d1d48270" xlink:to="loc_us-gaap_ClassOfTreasuryStockTable_425692ea-9217-494c-bd5d-af0f2cb570b5" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementClassOfStockAxis_b6220829-03db-47fd-bee2-587eed44980d" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_StatementClassOfStockAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ClassOfTreasuryStockTable_425692ea-9217-494c-bd5d-af0f2cb570b5" xlink:to="loc_us-gaap_StatementClassOfStockAxis_b6220829-03db-47fd-bee2-587eed44980d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_b6220829-03db-47fd-bee2-587eed44980d_default" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementClassOfStockAxis_b6220829-03db-47fd-bee2-587eed44980d" xlink:to="loc_us-gaap_ClassOfStockDomain_b6220829-03db-47fd-bee2-587eed44980d_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ClassOfStockDomain_ce1f99f5-0f80-4401-b2db-66e1659c7b25" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ClassOfStockDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementClassOfStockAxis_b6220829-03db-47fd-bee2-587eed44980d" xlink:to="loc_us-gaap_ClassOfStockDomain_ce1f99f5-0f80-4401-b2db-66e1659c7b25" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareRepurchaseProgramAxis_4a824031-476f-416b-a3a1-00aa8425f4ed" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ShareRepurchaseProgramAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ClassOfTreasuryStockTable_425692ea-9217-494c-bd5d-af0f2cb570b5" xlink:to="loc_us-gaap_ShareRepurchaseProgramAxis_4a824031-476f-416b-a3a1-00aa8425f4ed" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareRepurchaseProgramDomain_4a824031-476f-416b-a3a1-00aa8425f4ed_default" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ShareRepurchaseProgramDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ShareRepurchaseProgramAxis_4a824031-476f-416b-a3a1-00aa8425f4ed" xlink:to="loc_us-gaap_ShareRepurchaseProgramDomain_4a824031-476f-416b-a3a1-00aa8425f4ed_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareRepurchaseProgramDomain_440d713a-491d-44ca-88a8-5b771aacd7e9" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ShareRepurchaseProgramDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ShareRepurchaseProgramAxis_4a824031-476f-416b-a3a1-00aa8425f4ed" xlink:to="loc_us-gaap_ShareRepurchaseProgramDomain_440d713a-491d-44ca-88a8-5b771aacd7e9" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/StockBasedCompensation" xlink:type="simple" xlink:href="mtrx-20200630.xsd#StockBasedCompensation"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/StockBasedCompensation" xlink:type="extended" id="if5fce529d9c14576aeaaad54fa89d5d4_StockBasedCompensation"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/StockBasedCompensationTables" xlink:type="simple" xlink:href="mtrx-20200630.xsd#StockBasedCompensationTables"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/StockBasedCompensationTables" xlink:type="extended" id="i3341464ddcc943f48c999c76cddb1e59_StockBasedCompensationTables"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/StockBasedCompensationDetailsTextual" xlink:type="simple" xlink:href="mtrx-20200630.xsd#StockBasedCompensationDetailsTextual"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/StockBasedCompensationDetailsTextual" xlink:type="extended" id="i19f0689e12104008a48dc0aef04c7c92_StockBasedCompensationDetailsTextual">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7203aeac-ac92-49ba-80be-d47f67854596" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensation_eba1df80-346c-44d6-bd2f-28b46782d629" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ShareBasedCompensation"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7203aeac-ac92-49ba-80be-d47f67854596" xlink:to="loc_us-gaap_ShareBasedCompensation_eba1df80-346c-44d6-bd2f-28b46782d629" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_e50eccd6-e5d6-4979-98dc-f3e77983e205" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7203aeac-ac92-49ba-80be-d47f67854596" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized_e50eccd6-e5d6-4979-98dc-f3e77983e205" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_8ba042c2-6923-44cd-9f7d-744521084e1a" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7203aeac-ac92-49ba-80be-d47f67854596" xlink:to="loc_us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1_8ba042c2-6923-44cd-9f7d-744521084e1a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount_5b7c80e6-c88e-4df8-a302-3c4b00e2067a" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7203aeac-ac92-49ba-80be-d47f67854596" xlink:to="loc_us-gaap_EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount_5b7c80e6-c88e-4df8-a302-3c4b00e2067a" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized_83821d70-2ff1-45c0-89e7-56c6a7120c76" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7203aeac-ac92-49ba-80be-d47f67854596" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized_83821d70-2ff1-45c0-89e7-56c6a7120c76" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_9cbf8774-629c-4375-bde1-808f5734d5cc" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7203aeac-ac92-49ba-80be-d47f67854596" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_9cbf8774-629c-4375-bde1-808f5734d5cc" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod_f2eb9fc1-c095-4804-90f7-4396a58a23a7" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7203aeac-ac92-49ba-80be-d47f67854596" xlink:to="loc_us-gaap_SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod_f2eb9fc1-c095-4804-90f7-4396a58a23a7" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue_d568ed3f-f4ca-4e15-b90f-512b410b77f5" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7203aeac-ac92-49ba-80be-d47f67854596" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue_d568ed3f-f4ca-4e15-b90f-512b410b77f5" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_207a0832-f465-4e7d-924f-e9bec9cfa4bc" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7203aeac-ac92-49ba-80be-d47f67854596" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriod1_207a0832-f465-4e7d-924f-e9bec9cfa4bc" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_ShareBasedCompensationArrangementByShareBasedPaymentAwardInstallmentPeriodForVesting_c99b6e99-dd8c-4af6-8d1b-1bc055767b85" xlink:href="mtrx-20200630.xsd#mtrx_ShareBasedCompensationArrangementByShareBasedPaymentAwardInstallmentPeriodForVesting"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7203aeac-ac92-49ba-80be-d47f67854596" xlink:to="loc_mtrx_ShareBasedCompensationArrangementByShareBasedPaymentAwardInstallmentPeriodForVesting_c99b6e99-dd8c-4af6-8d1b-1bc055767b85" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_Vestingperiodretirementeligibleemployees_0c246de6-db73-4be1-a6ce-3f02c50126e3" xlink:href="mtrx-20200630.xsd#mtrx_Vestingperiodretirementeligibleemployees"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7203aeac-ac92-49ba-80be-d47f67854596" xlink:to="loc_mtrx_Vestingperiodretirementeligibleemployees_0c246de6-db73-4be1-a6ce-3f02c50126e3" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriodOfDirectorAwards_3096c715-32a1-449f-bce6-6ff13b343ff4" xlink:href="mtrx-20200630.xsd#mtrx_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriodOfDirectorAwards"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7203aeac-ac92-49ba-80be-d47f67854596" xlink:to="loc_mtrx_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingPeriodOfDirectorAwards_3096c715-32a1-449f-bce6-6ff13b343ff4" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardDescriptionofVestingPeriodofDirectorAwards_d9fc5605-3eca-4d1b-b4c8-733adfd62916" xlink:href="mtrx-20200630.xsd#mtrx_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardDescriptionofVestingPeriodofDirectorAwards"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7203aeac-ac92-49ba-80be-d47f67854596" xlink:to="loc_mtrx_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardDescriptionofVestingPeriodofDirectorAwards_d9fc5605-3eca-4d1b-b4c8-733adfd62916" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_PayoutAsPercentageOfOriginalAwardMinimum_32684b64-c37f-4cba-b68b-0270c463cdc3" xlink:href="mtrx-20200630.xsd#mtrx_PayoutAsPercentageOfOriginalAwardMinimum"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7203aeac-ac92-49ba-80be-d47f67854596" xlink:to="loc_mtrx_PayoutAsPercentageOfOriginalAwardMinimum_32684b64-c37f-4cba-b68b-0270c463cdc3" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_PayoutAsPercentageOfOriginalAwardMaximum_20af30f9-c7bd-4d40-9a96-9181e098fdf2" xlink:href="mtrx-20200630.xsd#mtrx_PayoutAsPercentageOfOriginalAwardMaximum"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7203aeac-ac92-49ba-80be-d47f67854596" xlink:to="loc_mtrx_PayoutAsPercentageOfOriginalAwardMaximum_20af30f9-c7bd-4d40-9a96-9181e098fdf2" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_MinimumThresholdSharesScheduledToVestForPerformanceBasedShares_b0b8c9a3-4968-43d2-9356-30d8b630c85d" xlink:href="mtrx-20200630.xsd#mtrx_MinimumThresholdSharesScheduledToVestForPerformanceBasedShares"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7203aeac-ac92-49ba-80be-d47f67854596" xlink:to="loc_mtrx_MinimumThresholdSharesScheduledToVestForPerformanceBasedShares_b0b8c9a3-4968-43d2-9356-30d8b630c85d" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsMethodUsed_fe727a4a-7a65-4fe2-b35d-864a8fb9db3d" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsMethodUsed"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7203aeac-ac92-49ba-80be-d47f67854596" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsMethodUsed_fe727a4a-7a65-4fe2-b35d-864a8fb9db3d" xlink:type="arc" order="16"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueMethodNumberofSimulationsUsed_4e9c1690-c881-4519-be50-a0be3e4f2d25" xlink:href="mtrx-20200630.xsd#mtrx_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueMethodNumberofSimulationsUsed"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7203aeac-ac92-49ba-80be-d47f67854596" xlink:to="loc_mtrx_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueMethodNumberofSimulationsUsed_4e9c1690-c881-4519-be50-a0be3e4f2d25" xlink:type="arc" order="17"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_ShareBasedCompensationArrangementByShareBasedPaymentAwardDeferredGrantsInPeriod_5a4f829b-0c51-4919-9681-3f2593cc6643" xlink:href="mtrx-20200630.xsd#mtrx_ShareBasedCompensationArrangementByShareBasedPaymentAwardDeferredGrantsInPeriod"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7203aeac-ac92-49ba-80be-d47f67854596" xlink:to="loc_mtrx_ShareBasedCompensationArrangementByShareBasedPaymentAwardDeferredGrantsInPeriod_5a4f829b-0c51-4919-9681-3f2593cc6643" xlink:type="arc" order="18"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_ShareBasedCompensationArrangementByShareBasedPaymentAwardDeferredWeightedAverageGrantDateFairValue_53912d13-f210-4340-b148-f16bd3d48575" xlink:href="mtrx-20200630.xsd#mtrx_ShareBasedCompensationArrangementByShareBasedPaymentAwardDeferredWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7203aeac-ac92-49ba-80be-d47f67854596" xlink:to="loc_mtrx_ShareBasedCompensationArrangementByShareBasedPaymentAwardDeferredWeightedAverageGrantDateFairValue_53912d13-f210-4340-b148-f16bd3d48575" xlink:type="arc" order="19"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_ShareBasedCompensationArrangementByShareBasedPaymentAwardDeferredSharesVestedAndReleased_57cbb3a1-0839-45cb-a23f-7fbddc9430dc" xlink:href="mtrx-20200630.xsd#mtrx_ShareBasedCompensationArrangementByShareBasedPaymentAwardDeferredSharesVestedAndReleased"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7203aeac-ac92-49ba-80be-d47f67854596" xlink:to="loc_mtrx_ShareBasedCompensationArrangementByShareBasedPaymentAwardDeferredSharesVestedAndReleased_57cbb3a1-0839-45cb-a23f-7fbddc9430dc" xlink:type="arc" order="20"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_ShareBasedCompensationArrangementByShareBasedPaymentAwardDeferredSharesVestedAndReleasedWeightedAverageGrantDateFairValue_d6c306b3-9208-4477-9209-abc77836ccdf" xlink:href="mtrx-20200630.xsd#mtrx_ShareBasedCompensationArrangementByShareBasedPaymentAwardDeferredSharesVestedAndReleasedWeightedAverageGrantDateFairValue"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7203aeac-ac92-49ba-80be-d47f67854596" xlink:to="loc_mtrx_ShareBasedCompensationArrangementByShareBasedPaymentAwardDeferredSharesVestedAndReleasedWeightedAverageGrantDateFairValue_d6c306b3-9208-4477-9209-abc77836ccdf" xlink:type="arc" order="21"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_5d813810-6bed-4887-89d2-f1d25e1add34" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems_7203aeac-ac92-49ba-80be-d47f67854596" xlink:to="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_5d813810-6bed-4887-89d2-f1d25e1add34" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameAxis_7eb00cda-542a-4f48-b217-1c0de97754ce" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_PlanNameAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_5d813810-6bed-4887-89d2-f1d25e1add34" xlink:to="loc_us-gaap_PlanNameAxis_7eb00cda-542a-4f48-b217-1c0de97754ce" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameDomain_7eb00cda-542a-4f48-b217-1c0de97754ce_default" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_PlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_PlanNameAxis_7eb00cda-542a-4f48-b217-1c0de97754ce" xlink:to="loc_us-gaap_PlanNameDomain_7eb00cda-542a-4f48-b217-1c0de97754ce_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PlanNameDomain_2d7a2b02-5fcf-4ae5-9960-9fcec0a4abd5" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_PlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_PlanNameAxis_7eb00cda-542a-4f48-b217-1c0de97754ce" xlink:to="loc_us-gaap_PlanNameDomain_2d7a2b02-5fcf-4ae5-9960-9fcec0a4abd5" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_MatrixServiceCompanys2004StockandIncentiveCompensationPlanMember_12ead54f-1611-44d0-960b-96aa31183da7" xlink:href="mtrx-20200630.xsd#mtrx_MatrixServiceCompanys2004StockandIncentiveCompensationPlanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PlanNameDomain_2d7a2b02-5fcf-4ae5-9960-9fcec0a4abd5" xlink:to="loc_mtrx_MatrixServiceCompanys2004StockandIncentiveCompensationPlanMember_12ead54f-1611-44d0-960b-96aa31183da7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_MatrixServiceCompanys2012StockandIncentiveCompensationPlanMember_d3d67adb-d799-4058-9c96-9f1fee397108" xlink:href="mtrx-20200630.xsd#mtrx_MatrixServiceCompanys2012StockandIncentiveCompensationPlanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PlanNameDomain_2d7a2b02-5fcf-4ae5-9960-9fcec0a4abd5" xlink:to="loc_mtrx_MatrixServiceCompanys2012StockandIncentiveCompensationPlanMember_d3d67adb-d799-4058-9c96-9f1fee397108" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_MatrixServiceCompany2016StockandIncentiveCompensationPlanMember_84b691dc-29ae-4ee1-b466-f2f00cc459a8" xlink:href="mtrx-20200630.xsd#mtrx_MatrixServiceCompany2016StockandIncentiveCompensationPlanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_PlanNameDomain_2d7a2b02-5fcf-4ae5-9960-9fcec0a4abd5" xlink:to="loc_mtrx_MatrixServiceCompany2016StockandIncentiveCompensationPlanMember_84b691dc-29ae-4ee1-b466-f2f00cc459a8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AwardTypeAxis_ef8f103f-4ad0-4441-afc5-9fdaf276d3b8" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_AwardTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_5d813810-6bed-4887-89d2-f1d25e1add34" xlink:to="loc_us-gaap_AwardTypeAxis_ef8f103f-4ad0-4441-afc5-9fdaf276d3b8" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_ef8f103f-4ad0-4441-afc5-9fdaf276d3b8_default" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AwardTypeAxis_ef8f103f-4ad0-4441-afc5-9fdaf276d3b8" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_ef8f103f-4ad0-4441-afc5-9fdaf276d3b8_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_1563d100-89d5-419f-910e-b06b416f2715" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AwardTypeAxis_ef8f103f-4ad0-4441-afc5-9fdaf276d3b8" xlink:to="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_1563d100-89d5-419f-910e-b06b416f2715" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_MarketBasedAwardsMember_ab6b47a0-8395-44b3-90d3-9193c7db4207" xlink:href="mtrx-20200630.xsd#mtrx_MarketBasedAwardsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_1563d100-89d5-419f-910e-b06b416f2715" xlink:to="loc_mtrx_MarketBasedAwardsMember_ab6b47a0-8395-44b3-90d3-9193c7db4207" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_Vestin2016Member_dc1d923b-ab58-46ce-b0a6-ce66e8cda873" xlink:href="mtrx-20200630.xsd#mtrx_Vestin2016Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_1563d100-89d5-419f-910e-b06b416f2715" xlink:to="loc_mtrx_Vestin2016Member_dc1d923b-ab58-46ce-b0a6-ce66e8cda873" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_Vestin2017Member_5c068d38-8f51-4b45-9d2e-8b78d5203d15" xlink:href="mtrx-20200630.xsd#mtrx_Vestin2017Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_1563d100-89d5-419f-910e-b06b416f2715" xlink:to="loc_mtrx_Vestin2017Member_5c068d38-8f51-4b45-9d2e-8b78d5203d15" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_Vestin2018Member_19234ded-af90-4903-975d-54052953a8c5" xlink:href="mtrx-20200630.xsd#mtrx_Vestin2018Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_1563d100-89d5-419f-910e-b06b416f2715" xlink:to="loc_mtrx_Vestin2018Member_19234ded-af90-4903-975d-54052953a8c5" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_VestIn2021Member_e6884ce8-9e0e-484b-98ec-3b062dbce4cf" xlink:href="mtrx-20200630.xsd#mtrx_VestIn2021Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_1563d100-89d5-419f-910e-b06b416f2715" xlink:to="loc_mtrx_VestIn2021Member_e6884ce8-9e0e-484b-98ec-3b062dbce4cf" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_VestIn2022Member_c7211177-d399-440e-b4e6-0060c023bd04" xlink:href="mtrx-20200630.xsd#mtrx_VestIn2022Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_1563d100-89d5-419f-910e-b06b416f2715" xlink:to="loc_mtrx_VestIn2022Member_c7211177-d399-440e-b4e6-0060c023bd04" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_VestIn2023Member_6c9d4cd1-0b43-4828-be7c-abf49a35f8c4" xlink:href="mtrx-20200630.xsd#mtrx_VestIn2023Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ShareBasedCompensationArrangementsByShareBasedPaymentAwardAwardTypeAndPlanNameDomain_1563d100-89d5-419f-910e-b06b416f2715" xlink:to="loc_mtrx_VestIn2023Member_6c9d4cd1-0b43-4828-be7c-abf49a35f8c4" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DeferredCompensationArrangementWithIndividualShareBasedPaymentsByTypeOfDeferredCompensationAxis_bef00fa3-1446-4e34-8c9c-507acce81ee3" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_DeferredCompensationArrangementWithIndividualShareBasedPaymentsByTypeOfDeferredCompensationAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_5d813810-6bed-4887-89d2-f1d25e1add34" xlink:to="loc_us-gaap_DeferredCompensationArrangementWithIndividualShareBasedPaymentsByTypeOfDeferredCompensationAxis_bef00fa3-1446-4e34-8c9c-507acce81ee3" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityBasedArrangementsIndividualContractsTypeOfDeferredCompensationDomain_bef00fa3-1446-4e34-8c9c-507acce81ee3_default" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_EquityBasedArrangementsIndividualContractsTypeOfDeferredCompensationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_DeferredCompensationArrangementWithIndividualShareBasedPaymentsByTypeOfDeferredCompensationAxis_bef00fa3-1446-4e34-8c9c-507acce81ee3" xlink:to="loc_us-gaap_EquityBasedArrangementsIndividualContractsTypeOfDeferredCompensationDomain_bef00fa3-1446-4e34-8c9c-507acce81ee3_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EquityBasedArrangementsIndividualContractsTypeOfDeferredCompensationDomain_eee472a8-8988-4678-8861-cd5bc9d30089" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_EquityBasedArrangementsIndividualContractsTypeOfDeferredCompensationDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_DeferredCompensationArrangementWithIndividualShareBasedPaymentsByTypeOfDeferredCompensationAxis_bef00fa3-1446-4e34-8c9c-507acce81ee3" xlink:to="loc_us-gaap_EquityBasedArrangementsIndividualContractsTypeOfDeferredCompensationDomain_eee472a8-8988-4678-8861-cd5bc9d30089" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_EmployeeAwardMember_36a21112-6058-4aef-9b02-2d42ca33a661" xlink:href="mtrx-20200630.xsd#mtrx_EmployeeAwardMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityBasedArrangementsIndividualContractsTypeOfDeferredCompensationDomain_eee472a8-8988-4678-8861-cd5bc9d30089" xlink:to="loc_mtrx_EmployeeAwardMember_36a21112-6058-4aef-9b02-2d42ca33a661" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_DirectorAwardsMember_9792cb41-d4ef-41d1-b1ae-16a48c772bd8" xlink:href="mtrx-20200630.xsd#mtrx_DirectorAwardsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EquityBasedArrangementsIndividualContractsTypeOfDeferredCompensationDomain_eee472a8-8988-4678-8861-cd5bc9d30089" xlink:to="loc_mtrx_DirectorAwardsMember_9792cb41-d4ef-41d1-b1ae-16a48c772bd8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeAxis_eb857fa7-5c80-481f-ab64-46be424ed9ff" xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_RangeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfShareBasedCompensationArrangementsByShareBasedPaymentAwardTable_5d813810-6bed-4887-89d2-f1d25e1add34" xlink:to="loc_srt_RangeAxis_eb857fa7-5c80-481f-ab64-46be424ed9ff" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_eb857fa7-5c80-481f-ab64-46be424ed9ff_default" xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_RangeAxis_eb857fa7-5c80-481f-ab64-46be424ed9ff" xlink:to="loc_srt_RangeMember_eb857fa7-5c80-481f-ab64-46be424ed9ff_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_RangeMember_44c570ec-cee7-4185-b64a-ba647ac38e2c" xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_RangeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_RangeAxis_eb857fa7-5c80-481f-ab64-46be424ed9ff" xlink:to="loc_srt_RangeMember_44c570ec-cee7-4185-b64a-ba647ac38e2c" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MinimumMember_f5e3c3da-4251-47e8-94ba-edae64634734" xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_MinimumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_44c570ec-cee7-4185-b64a-ba647ac38e2c" xlink:to="loc_srt_MinimumMember_f5e3c3da-4251-47e8-94ba-edae64634734" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MaximumMember_b1048972-a8bf-481a-b06d-f9b8f7ced803" xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_MaximumMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_RangeMember_44c570ec-cee7-4185-b64a-ba647ac38e2c" xlink:to="loc_srt_MaximumMember_b1048972-a8bf-481a-b06d-f9b8f7ced803" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/StockBasedCompensationDetails" xlink:type="simple" xlink:href="mtrx-20200630.xsd#StockBasedCompensationDetails"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/StockBasedCompensationDetails" xlink:type="extended" id="icae10d936e4c48d1af20e5df46b30bad_StockBasedCompensationDetails"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/StockBasedCompensationDetails1" xlink:type="simple" xlink:href="mtrx-20200630.xsd#StockBasedCompensationDetails1"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/StockBasedCompensationDetails1" xlink:type="extended" id="ie5e2cbcac2a2464aa1c2dad5ee663c1d_StockBasedCompensationDetails1"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/StockBasedCompensationDetails2" xlink:type="simple" xlink:href="mtrx-20200630.xsd#StockBasedCompensationDetails2"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/StockBasedCompensationDetails2" xlink:type="extended" id="if65ca7dd71f5477a8c3f1eb05e2bae15_StockBasedCompensationDetails2"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/EarningsperCommonShare" xlink:type="simple" xlink:href="mtrx-20200630.xsd#EarningsperCommonShare"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/EarningsperCommonShare" xlink:type="extended" id="i005b41ba2ad441f4b7e9721479996238_EarningsperCommonShare"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/EarningsperCommonShareTables" xlink:type="simple" xlink:href="mtrx-20200630.xsd#EarningsperCommonShareTables"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/EarningsperCommonShareTables" xlink:type="extended" id="i65b3d7056c84440c96cdb6872e2aaf33_EarningsperCommonShareTables"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/EarningsperCommonShareDetails" xlink:type="simple" xlink:href="mtrx-20200630.xsd#EarningsperCommonShareDetails"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/EarningsperCommonShareDetails" xlink:type="extended" id="i56fc424378594396931a2277ab0b1153_EarningsperCommonShareDetails"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/EarningsperCommonShareDetails1" xlink:type="simple" xlink:href="mtrx-20200630.xsd#EarningsperCommonShareDetails1"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/EarningsperCommonShareDetails1" xlink:type="extended" id="i9e53e96e014f4b10abda6aac088c43fc_EarningsperCommonShareDetails1">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_0144de9e-b07c-4318-aca5-4f1bde889db7" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_AntidilutiveSecuritiesExcludedFromComputationOfDilutedEarningsPerShareAbstract_dd2a5241-c3d1-49a9-8da7-ffbdb853f7d0" xlink:href="mtrx-20200630.xsd#mtrx_AntidilutiveSecuritiesExcludedFromComputationOfDilutedEarningsPerShareAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_0144de9e-b07c-4318-aca5-4f1bde889db7" xlink:to="loc_mtrx_AntidilutiveSecuritiesExcludedFromComputationOfDilutedEarningsPerShareAbstract_dd2a5241-c3d1-49a9-8da7-ffbdb853f7d0" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_326e2bbe-eb34-43fc-ada9-f4a48d9abcd8" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtrx_AntidilutiveSecuritiesExcludedFromComputationOfDilutedEarningsPerShareAbstract_dd2a5241-c3d1-49a9-8da7-ffbdb853f7d0" xlink:to="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount_326e2bbe-eb34-43fc-ada9-f4a48d9abcd8" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_00cdf3d0-60fd-4064-8658-3265c4954719" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareLineItems_0144de9e-b07c-4318-aca5-4f1bde889db7" xlink:to="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_00cdf3d0-60fd-4064-8658-3265c4954719" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_5196b67f-ea48-41d4-a2a7-12e917475a65" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfAntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareTable_00cdf3d0-60fd-4064-8658-3265c4954719" xlink:to="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_5196b67f-ea48-41d4-a2a7-12e917475a65" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesNameDomain_5196b67f-ea48-41d4-a2a7-12e917475a65_default" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_AntidilutiveSecuritiesNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_5196b67f-ea48-41d4-a2a7-12e917475a65" xlink:to="loc_us-gaap_AntidilutiveSecuritiesNameDomain_5196b67f-ea48-41d4-a2a7-12e917475a65_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AntidilutiveSecuritiesNameDomain_76cdbb97-223a-4961-8d9d-7a4d304ce02b" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_AntidilutiveSecuritiesNameDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareByAntidilutiveSecuritiesAxis_5196b67f-ea48-41d4-a2a7-12e917475a65" xlink:to="loc_us-gaap_AntidilutiveSecuritiesNameDomain_76cdbb97-223a-4961-8d9d-7a4d304ce02b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EmployeeStockOptionMember_d67cb7ac-366e-418a-896d-e3fad93d1617" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_EmployeeStockOptionMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_76cdbb97-223a-4961-8d9d-7a4d304ce02b" xlink:to="loc_us-gaap_EmployeeStockOptionMember_d67cb7ac-366e-418a-896d-e3fad93d1617" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_NonvestedDeferredSharesMember_210cfb7f-8a79-4ca0-a732-b1c47b513d01" xlink:href="mtrx-20200630.xsd#mtrx_NonvestedDeferredSharesMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_AntidilutiveSecuritiesNameDomain_76cdbb97-223a-4961-8d9d-7a4d304ce02b" xlink:to="loc_mtrx_NonvestedDeferredSharesMember_210cfb7f-8a79-4ca0-a732-b1c47b513d01" xlink:type="arc" order="1"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/EmployeeBenefitPlans" xlink:type="simple" xlink:href="mtrx-20200630.xsd#EmployeeBenefitPlans"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/EmployeeBenefitPlans" xlink:type="extended" id="ifd7effc6954241cab1698b9e424ae890_EmployeeBenefitPlans"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/EmployeeBenefitPlansTables" xlink:type="simple" xlink:href="mtrx-20200630.xsd#EmployeeBenefitPlansTables"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/EmployeeBenefitPlansTables" xlink:type="extended" id="ic763338baee6420494c9b6e0c0c87796_EmployeeBenefitPlansTables"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/EmployeeBenefitPlansDetailsTextual" xlink:type="simple" xlink:href="mtrx-20200630.xsd#EmployeeBenefitPlansDetailsTextual"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/EmployeeBenefitPlansDetailsTextual" xlink:type="extended" id="i01760bf847f04c06a5febe2c08976246_EmployeeBenefitPlansDetailsTextual">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MultiemployerPlansLineItems_bffa81d2-7143-4835-83f6-d926a828712d" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_MultiemployerPlansLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_PercentageOfPlanFunded_eca27bc9-878a-4f00-bdc4-2b5af9a57541" xlink:href="mtrx-20200630.xsd#mtrx_PercentageOfPlanFunded"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MultiemployerPlansLineItems_bffa81d2-7143-4835-83f6-d926a828712d" xlink:to="loc_mtrx_PercentageOfPlanFunded_eca27bc9-878a-4f00-bdc4-2b5af9a57541" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_DescriptionOfFundedPortionOfPlan_13d4ea10-d36e-406c-93c1-8c2ddaa371ab" xlink:href="mtrx-20200630.xsd#mtrx_DescriptionOfFundedPortionOfPlan"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MultiemployerPlansLineItems_bffa81d2-7143-4835-83f6-d926a828712d" xlink:to="loc_mtrx_DescriptionOfFundedPortionOfPlan_13d4ea10-d36e-406c-93c1-8c2ddaa371ab" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfMultiemployerPlansTable_7c05104b-a610-4bac-8ec0-0ded435580b3" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ScheduleOfMultiemployerPlansTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_MultiemployerPlansLineItems_bffa81d2-7143-4835-83f6-d926a828712d" xlink:to="loc_us-gaap_ScheduleOfMultiemployerPlansTable_7c05104b-a610-4bac-8ec0-0ded435580b3" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetirementPlanTypeAxis_8e59721f-16ad-45a7-ae1c-e5e0a2278d24" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_RetirementPlanTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfMultiemployerPlansTable_7c05104b-a610-4bac-8ec0-0ded435580b3" xlink:to="loc_us-gaap_RetirementPlanTypeAxis_8e59721f-16ad-45a7-ae1c-e5e0a2278d24" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetirementPlanTypeDomain_8e59721f-16ad-45a7-ae1c-e5e0a2278d24_default" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_RetirementPlanTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RetirementPlanTypeAxis_8e59721f-16ad-45a7-ae1c-e5e0a2278d24" xlink:to="loc_us-gaap_RetirementPlanTypeDomain_8e59721f-16ad-45a7-ae1c-e5e0a2278d24_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetirementPlanTypeDomain_d544f712-6524-4303-be36-ea4f2ef52a57" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_RetirementPlanTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RetirementPlanTypeAxis_8e59721f-16ad-45a7-ae1c-e5e0a2278d24" xlink:to="loc_us-gaap_RetirementPlanTypeDomain_d544f712-6524-4303-be36-ea4f2ef52a57" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_PlumbersandPipefittersLocalUnionSevenFourPensionFundMember_22836c99-8bd7-4976-9b27-0d0e6289b0a3" xlink:href="mtrx-20200630.xsd#mtrx_PlumbersandPipefittersLocalUnionSevenFourPensionFundMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RetirementPlanTypeDomain_d544f712-6524-4303-be36-ea4f2ef52a57" xlink:to="loc_mtrx_PlumbersandPipefittersLocalUnionSevenFourPensionFundMember_22836c99-8bd7-4976-9b27-0d0e6289b0a3" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_MultiemployerPlanZoneByTypeAxis_52f48eda-a8ca-4ec4-9cfe-723cd9a2770c" xlink:href="mtrx-20200630.xsd#mtrx_MultiemployerPlanZoneByTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfMultiemployerPlansTable_7c05104b-a610-4bac-8ec0-0ded435580b3" xlink:to="loc_mtrx_MultiemployerPlanZoneByTypeAxis_52f48eda-a8ca-4ec4-9cfe-723cd9a2770c" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_MultiemployerPlanZoneByTypeDomain_52f48eda-a8ca-4ec4-9cfe-723cd9a2770c_default" xlink:href="mtrx-20200630.xsd#mtrx_MultiemployerPlanZoneByTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_mtrx_MultiemployerPlanZoneByTypeAxis_52f48eda-a8ca-4ec4-9cfe-723cd9a2770c" xlink:to="loc_mtrx_MultiemployerPlanZoneByTypeDomain_52f48eda-a8ca-4ec4-9cfe-723cd9a2770c_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_MultiemployerPlanZoneByTypeDomain_53f8ab35-9b22-4ce0-b9ae-2a1f17259fa6" xlink:href="mtrx-20200630.xsd#mtrx_MultiemployerPlanZoneByTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_mtrx_MultiemployerPlanZoneByTypeAxis_52f48eda-a8ca-4ec4-9cfe-723cd9a2770c" xlink:to="loc_mtrx_MultiemployerPlanZoneByTypeDomain_53f8ab35-9b22-4ce0-b9ae-2a1f17259fa6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_ZoneRedMember_3167b487-78ad-4dee-bbe5-3b4251840389" xlink:href="mtrx-20200630.xsd#mtrx_ZoneRedMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtrx_MultiemployerPlanZoneByTypeDomain_53f8ab35-9b22-4ce0-b9ae-2a1f17259fa6" xlink:to="loc_mtrx_ZoneRedMember_3167b487-78ad-4dee-bbe5-3b4251840389" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_ZoneYellowMember_606825ba-e22a-413f-a0c3-a36886480494" xlink:href="mtrx-20200630.xsd#mtrx_ZoneYellowMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtrx_MultiemployerPlanZoneByTypeDomain_53f8ab35-9b22-4ce0-b9ae-2a1f17259fa6" xlink:to="loc_mtrx_ZoneYellowMember_606825ba-e22a-413f-a0c3-a36886480494" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_ZoneGreenMember_642163c0-16f9-4598-82ea-50431ae38d86" xlink:href="mtrx-20200630.xsd#mtrx_ZoneGreenMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtrx_MultiemployerPlanZoneByTypeDomain_53f8ab35-9b22-4ce0-b9ae-2a1f17259fa6" xlink:to="loc_mtrx_ZoneGreenMember_642163c0-16f9-4598-82ea-50431ae38d86" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/EmployeeBenefitPlansDetails" xlink:type="simple" xlink:href="mtrx-20200630.xsd#EmployeeBenefitPlansDetails"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/EmployeeBenefitPlansDetails" xlink:type="extended" id="ic724b20fa480434197f7250648bf8e8c_EmployeeBenefitPlansDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MultiemployerPlansLineItems_b1366b3a-19f6-4576-8443-8311de7aa543" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_MultiemployerPlansLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_MultiemployerPlansNumber_8695022e-a3b3-40c1-9bf2-ccecbe32f2e7" xlink:href="mtrx-20200630.xsd#mtrx_MultiemployerPlansNumber"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MultiemployerPlansLineItems_b1366b3a-19f6-4576-8443-8311de7aa543" xlink:to="loc_mtrx_MultiemployerPlansNumber_8695022e-a3b3-40c1-9bf2-ccecbe32f2e7" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MultiemployerPlanPensionSignificantCertifiedZoneStatusFixedList_393750ec-d20a-4d69-af98-14af0a1a871b" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_MultiemployerPlanPensionSignificantCertifiedZoneStatusFixedList"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MultiemployerPlansLineItems_b1366b3a-19f6-4576-8443-8311de7aa543" xlink:to="loc_us-gaap_MultiemployerPlanPensionSignificantCertifiedZoneStatusFixedList_393750ec-d20a-4d69-af98-14af0a1a871b" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_MultiemployerPlansCertifiedZoneStatusDescription_88fd39cb-df8a-4d36-bd25-03e56f3db3e7" xlink:href="mtrx-20200630.xsd#mtrx_MultiemployerPlansCertifiedZoneStatusDescription"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MultiemployerPlansLineItems_b1366b3a-19f6-4576-8443-8311de7aa543" xlink:to="loc_mtrx_MultiemployerPlansCertifiedZoneStatusDescription_88fd39cb-df8a-4d36-bd25-03e56f3db3e7" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MultiemployerPlanPensionSignificantFundingImprovementOrRehabilitationPlanImplementationStatusFixedList_7c45bc25-e85c-46ec-9c87-c63658e5d466" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_MultiemployerPlanPensionSignificantFundingImprovementOrRehabilitationPlanImplementationStatusFixedList"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MultiemployerPlansLineItems_b1366b3a-19f6-4576-8443-8311de7aa543" xlink:to="loc_us-gaap_MultiemployerPlanPensionSignificantFundingImprovementOrRehabilitationPlanImplementationStatusFixedList_7c45bc25-e85c-46ec-9c87-c63658e5d466" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MultiemployerPlanPensionSignificantEmployerContributionCost_307cfc62-ae1b-4f4c-8c78-32090dea9f71" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_MultiemployerPlanPensionSignificantEmployerContributionCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MultiemployerPlansLineItems_b1366b3a-19f6-4576-8443-8311de7aa543" xlink:to="loc_us-gaap_MultiemployerPlanPensionSignificantEmployerContributionCost_307cfc62-ae1b-4f4c-8c78-32090dea9f71" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MultiemployerPlanPensionInsignificantEmployerContributionCost_5557078b-f6eb-4cda-b67d-4ae24f371873" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_MultiemployerPlanPensionInsignificantEmployerContributionCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MultiemployerPlansLineItems_b1366b3a-19f6-4576-8443-8311de7aa543" xlink:to="loc_us-gaap_MultiemployerPlanPensionInsignificantEmployerContributionCost_5557078b-f6eb-4cda-b67d-4ae24f371873" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MultiemployerPlanEmployerContributionCost_20332522-4db4-4595-82cb-0ef534cae5d7" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_MultiemployerPlanEmployerContributionCost"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MultiemployerPlansLineItems_b1366b3a-19f6-4576-8443-8311de7aa543" xlink:to="loc_us-gaap_MultiemployerPlanEmployerContributionCost_20332522-4db4-4595-82cb-0ef534cae5d7" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MultiemployerPlanPensionSignificantSurchargeFixedList_4e7296fd-344e-4fd2-984b-a08932de91bd" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_MultiemployerPlanPensionSignificantSurchargeFixedList"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MultiemployerPlansLineItems_b1366b3a-19f6-4576-8443-8311de7aa543" xlink:to="loc_us-gaap_MultiemployerPlanPensionSignificantSurchargeFixedList_4e7296fd-344e-4fd2-984b-a08932de91bd" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MultiemployerPlanPensionSignificantCollectiveBargainingArrangementExpirationDate_a7469db8-4ada-4360-9a03-79a61b7d73e3" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_MultiemployerPlanPensionSignificantCollectiveBargainingArrangementExpirationDate"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MultiemployerPlansLineItems_b1366b3a-19f6-4576-8443-8311de7aa543" xlink:to="loc_us-gaap_MultiemployerPlanPensionSignificantCollectiveBargainingArrangementExpirationDate_a7469db8-4ada-4360-9a03-79a61b7d73e3" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MultiemployerPlansCollectiveBargainingArrangementExpirationDateDescription_e98e0040-d378-419f-b721-83cda4ed6408" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_MultiemployerPlansCollectiveBargainingArrangementExpirationDateDescription"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MultiemployerPlansLineItems_b1366b3a-19f6-4576-8443-8311de7aa543" xlink:to="loc_us-gaap_MultiemployerPlansCollectiveBargainingArrangementExpirationDateDescription_e98e0040-d378-419f-b721-83cda4ed6408" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfMultiemployerPlansTable_81a0ecbc-6eb2-4b56-b3d7-cd1204068275" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ScheduleOfMultiemployerPlansTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_MultiemployerPlansLineItems_b1366b3a-19f6-4576-8443-8311de7aa543" xlink:to="loc_us-gaap_ScheduleOfMultiemployerPlansTable_81a0ecbc-6eb2-4b56-b3d7-cd1204068275" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetirementPlanTypeAxis_b915c199-455d-457d-87ac-d482c47642da" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_RetirementPlanTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfMultiemployerPlansTable_81a0ecbc-6eb2-4b56-b3d7-cd1204068275" xlink:to="loc_us-gaap_RetirementPlanTypeAxis_b915c199-455d-457d-87ac-d482c47642da" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetirementPlanTypeDomain_b915c199-455d-457d-87ac-d482c47642da_default" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_RetirementPlanTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_RetirementPlanTypeAxis_b915c199-455d-457d-87ac-d482c47642da" xlink:to="loc_us-gaap_RetirementPlanTypeDomain_b915c199-455d-457d-87ac-d482c47642da_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RetirementPlanTypeDomain_816e4fa8-3999-4b4a-b020-367acaa54592" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_RetirementPlanTypeDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_RetirementPlanTypeAxis_b915c199-455d-457d-87ac-d482c47642da" xlink:to="loc_us-gaap_RetirementPlanTypeDomain_816e4fa8-3999-4b4a-b020-367acaa54592" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_BoilermakerBlacksmithNationalPensionTrustMember_e853d06e-abb3-40cb-9903-91c5197a1ba5" xlink:href="mtrx-20200630.xsd#mtrx_BoilermakerBlacksmithNationalPensionTrustMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RetirementPlanTypeDomain_816e4fa8-3999-4b4a-b020-367acaa54592" xlink:to="loc_mtrx_BoilermakerBlacksmithNationalPensionTrustMember_e853d06e-abb3-40cb-9903-91c5197a1ba5" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_JointPensionFundLocalUnionOneSixFourIbewMember_8ad3ea37-bc07-4f74-b701-e7f01dcfdb07" xlink:href="mtrx-20200630.xsd#mtrx_JointPensionFundLocalUnionOneSixFourIbewMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RetirementPlanTypeDomain_816e4fa8-3999-4b4a-b020-367acaa54592" xlink:to="loc_mtrx_JointPensionFundLocalUnionOneSixFourIbewMember_8ad3ea37-bc07-4f74-b701-e7f01dcfdb07" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_JointPensionFundLocalUnionNumberOneZeroTwoMemberDomain_45c91977-85a0-4b61-a1f8-7cb2750b29b1" xlink:href="mtrx-20200630.xsd#mtrx_JointPensionFundLocalUnionNumberOneZeroTwoMemberDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RetirementPlanTypeDomain_816e4fa8-3999-4b4a-b020-367acaa54592" xlink:to="loc_mtrx_JointPensionFundLocalUnionNumberOneZeroTwoMemberDomain_45c91977-85a0-4b61-a1f8-7cb2750b29b1" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_IBEWLocalFourFiveSixPensionPlanMemberDomain_b5c0fe9d-e8fe-47ac-b276-a7a2a8b87eae" xlink:href="mtrx-20200630.xsd#mtrx_IBEWLocalFourFiveSixPensionPlanMemberDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RetirementPlanTypeDomain_816e4fa8-3999-4b4a-b020-367acaa54592" xlink:to="loc_mtrx_IBEWLocalFourFiveSixPensionPlanMemberDomain_b5c0fe9d-e8fe-47ac-b276-a7a2a8b87eae" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_LocalThreeFiveOneIbewPensionPlanMember_18a49f4b-1d30-4804-a72a-3b458a859008" xlink:href="mtrx-20200630.xsd#mtrx_LocalThreeFiveOneIbewPensionPlanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RetirementPlanTypeDomain_816e4fa8-3999-4b4a-b020-367acaa54592" xlink:to="loc_mtrx_LocalThreeFiveOneIbewPensionPlanMember_18a49f4b-1d30-4804-a72a-3b458a859008" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_SteamfittersLocalUnionNumberFourTwoZeroPensionPlanMemberDomain_65d14b78-0d16-4455-a77b-ec2679245bc3" xlink:href="mtrx-20200630.xsd#mtrx_SteamfittersLocalUnionNumberFourTwoZeroPensionPlanMemberDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RetirementPlanTypeDomain_816e4fa8-3999-4b4a-b020-367acaa54592" xlink:to="loc_mtrx_SteamfittersLocalUnionNumberFourTwoZeroPensionPlanMemberDomain_65d14b78-0d16-4455-a77b-ec2679245bc3" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_IBEWLocalUnionNineEightPensionPlanMember_66a6ab42-db3d-498b-a3ec-874f5e6120aa" xlink:href="mtrx-20200630.xsd#mtrx_IBEWLocalUnionNineEightPensionPlanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RetirementPlanTypeDomain_816e4fa8-3999-4b4a-b020-367acaa54592" xlink:to="loc_mtrx_IBEWLocalUnionNineEightPensionPlanMember_66a6ab42-db3d-498b-a3ec-874f5e6120aa" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_IndianaLaborersPensionFundDomain_d1644e0d-8b58-4cb1-8117-02af17d9eb93" xlink:href="mtrx-20200630.xsd#mtrx_IndianaLaborersPensionFundDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RetirementPlanTypeDomain_816e4fa8-3999-4b4a-b020-367acaa54592" xlink:to="loc_mtrx_IndianaLaborersPensionFundDomain_d1644e0d-8b58-4cb1-8117-02af17d9eb93" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_IronworkersMidAmericaPensionPlanMember_ed76ea6f-ab87-4580-8fe5-a7e5a8dd60bc" xlink:href="mtrx-20200630.xsd#mtrx_IronworkersMidAmericaPensionPlanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RetirementPlanTypeDomain_816e4fa8-3999-4b4a-b020-367acaa54592" xlink:to="loc_mtrx_IronworkersMidAmericaPensionPlanMember_ed76ea6f-ab87-4580-8fe5-a7e5a8dd60bc" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_PipefittersRetirementFundLocalFiveNineSevenMember_8aca8aaa-10d2-4208-90e0-865d81c9db10" xlink:href="mtrx-20200630.xsd#mtrx_PipefittersRetirementFundLocalFiveNineSevenMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RetirementPlanTypeDomain_816e4fa8-3999-4b4a-b020-367acaa54592" xlink:to="loc_mtrx_PipefittersRetirementFundLocalFiveNineSevenMember_8aca8aaa-10d2-4208-90e0-865d81c9db10" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_IronWorkersPensionPlanofWesternPennsylvaniaLocal3Member_53e630d6-2567-4d5f-9f50-f409aa21addc" xlink:href="mtrx-20200630.xsd#mtrx_IronWorkersPensionPlanofWesternPennsylvaniaLocal3Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RetirementPlanTypeDomain_816e4fa8-3999-4b4a-b020-367acaa54592" xlink:to="loc_mtrx_IronWorkersPensionPlanofWesternPennsylvaniaLocal3Member_53e630d6-2567-4d5f-9f50-f409aa21addc" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_IronWorkersPensionPlanLoc.55Member_27f14af4-9b6e-42ea-a7c9-5ffe9a4a08c9" xlink:href="mtrx-20200630.xsd#mtrx_IronWorkersPensionPlanLoc.55Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RetirementPlanTypeDomain_816e4fa8-3999-4b4a-b020-367acaa54592" xlink:to="loc_mtrx_IronWorkersPensionPlanLoc.55Member_27f14af4-9b6e-42ea-a7c9-5ffe9a4a08c9" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_NationalElectricalBenefitFundLocal488And126Member_49b90377-9222-4904-b07d-b7c72a65de48" xlink:href="mtrx-20200630.xsd#mtrx_NationalElectricalBenefitFundLocal488And126Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RetirementPlanTypeDomain_816e4fa8-3999-4b4a-b020-367acaa54592" xlink:to="loc_mtrx_NationalElectricalBenefitFundLocal488And126Member_49b90377-9222-4904-b07d-b7c72a65de48" xlink:type="arc" order="12"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_ConnecticutPlumbersandPipefittersPensionFundLocal777Member_bd48d0e4-766f-4986-b25b-92ed834ff0d8" xlink:href="mtrx-20200630.xsd#mtrx_ConnecticutPlumbersandPipefittersPensionFundLocal777Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RetirementPlanTypeDomain_816e4fa8-3999-4b4a-b020-367acaa54592" xlink:to="loc_mtrx_ConnecticutPlumbersandPipefittersPensionFundLocal777Member_bd48d0e4-766f-4986-b25b-92ed834ff0d8" xlink:type="arc" order="13"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_NorthwesternOhioPlumbersAndPipeFittersLocal50Member_db11afbf-faae-4822-af61-fee720a95e0b" xlink:href="mtrx-20200630.xsd#mtrx_NorthwesternOhioPlumbersAndPipeFittersLocal50Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RetirementPlanTypeDomain_816e4fa8-3999-4b4a-b020-367acaa54592" xlink:to="loc_mtrx_NorthwesternOhioPlumbersAndPipeFittersLocal50Member_db11afbf-faae-4822-af61-fee720a95e0b" xlink:type="arc" order="14"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_OhioCarpentersPensionFundLocal1090and351Member_df1e280e-3c7b-4f3c-b7d7-2d1b3e63b406" xlink:href="mtrx-20200630.xsd#mtrx_OhioCarpentersPensionFundLocal1090and351Member"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RetirementPlanTypeDomain_816e4fa8-3999-4b4a-b020-367acaa54592" xlink:to="loc_mtrx_OhioCarpentersPensionFundLocal1090and351Member_df1e280e-3c7b-4f3c-b7d7-2d1b3e63b406" xlink:type="arc" order="15"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_IBEWLocal654PensionPlanMember_c7c9e05d-add8-4d5f-92b2-d7087e0288d9" xlink:href="mtrx-20200630.xsd#mtrx_IBEWLocal654PensionPlanMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RetirementPlanTypeDomain_816e4fa8-3999-4b4a-b020-367acaa54592" xlink:to="loc_mtrx_IBEWLocal654PensionPlanMember_c7c9e05d-add8-4d5f-92b2-d7087e0288d9" xlink:type="arc" order="16"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/SegmentInformation" xlink:type="simple" xlink:href="mtrx-20200630.xsd#SegmentInformation"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/SegmentInformation" xlink:type="extended" id="i1c8835cb329c42f99eec1eeb2f7372ed_SegmentInformation"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/SegmentInformationTables" xlink:type="simple" xlink:href="mtrx-20200630.xsd#SegmentInformationTables"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/SegmentInformationTables" xlink:type="extended" id="i8732a82e93984d328b56fdf932ce246e_SegmentInformationTables"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/SegmentInformationDetails" xlink:type="simple" xlink:href="mtrx-20200630.xsd#SegmentInformationDetails"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/SegmentInformationDetails" xlink:type="extended" id="i0e7ea4fe9c554beba00d2cb07c5adca2_SegmentInformationDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingInformationLineItems_2810385f-b672-4b02-903f-1ce4549aae9a" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_SegmentReportingInformationLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentReportingInformationProfitLossAbstract_c34e0d59-2b9b-4e90-8abb-67bc99654bd8" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_SegmentReportingInformationProfitLossAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_2810385f-b672-4b02-903f-1ce4549aae9a" xlink:to="loc_us-gaap_SegmentReportingInformationProfitLossAbstract_c34e0d59-2b9b-4e90-8abb-67bc99654bd8" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_Grossrevenues_542984a4-317a-4983-a826-6e30758a99dd" xlink:href="mtrx-20200630.xsd#mtrx_Grossrevenues"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationProfitLossAbstract_c34e0d59-2b9b-4e90-8abb-67bc99654bd8" xlink:to="loc_mtrx_Grossrevenues_542984a4-317a-4983-a826-6e30758a99dd" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Revenues_ec717104-ac57-4821-904d-e0569e3bf73d" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_Revenues"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationProfitLossAbstract_c34e0d59-2b9b-4e90-8abb-67bc99654bd8" xlink:to="loc_us-gaap_Revenues_ec717104-ac57-4821-904d-e0569e3bf73d" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_GrossProfit_7de00b1e-cde1-4210-8945-5844b2a0fdf5" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_GrossProfit"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationProfitLossAbstract_c34e0d59-2b9b-4e90-8abb-67bc99654bd8" xlink:to="loc_us-gaap_GrossProfit_7de00b1e-cde1-4210-8945-5844b2a0fdf5" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringSettlementAndImpairmentProvisions_b6f4578c-c720-4c87-a83a-f83c0fb58664" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_RestructuringSettlementAndImpairmentProvisions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationProfitLossAbstract_c34e0d59-2b9b-4e90-8abb-67bc99654bd8" xlink:to="loc_us-gaap_RestructuringSettlementAndImpairmentProvisions_b6f4578c-c720-4c87-a83a-f83c0fb58664" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingIncomeLoss_b01ad130-e152-4f52-bb4b-2c14ed3e4660" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_OperatingIncomeLoss"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationProfitLossAbstract_c34e0d59-2b9b-4e90-8abb-67bc99654bd8" xlink:to="loc_us-gaap_OperatingIncomeLoss_b01ad130-e152-4f52-bb4b-2c14ed3e4660" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_Assets_8019e0ec-b714-4f3b-bf51-68df693c24e7" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_Assets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationProfitLossAbstract_c34e0d59-2b9b-4e90-8abb-67bc99654bd8" xlink:to="loc_us-gaap_Assets_8019e0ec-b714-4f3b-bf51-68df693c24e7" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_df5a37a0-c317-448e-8b06-95840d3eab7c" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_PaymentsToAcquirePropertyPlantAndEquipment"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationProfitLossAbstract_c34e0d59-2b9b-4e90-8abb-67bc99654bd8" xlink:to="loc_us-gaap_PaymentsToAcquirePropertyPlantAndEquipment_df5a37a0-c317-448e-8b06-95840d3eab7c" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_DepreciationDepletionAndAmortization_b80a2f7d-d9dc-43e4-bec7-42beb94ac219" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_DepreciationDepletionAndAmortization"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentReportingInformationProfitLossAbstract_c34e0d59-2b9b-4e90-8abb-67bc99654bd8" xlink:to="loc_us-gaap_DepreciationDepletionAndAmortization_b80a2f7d-d9dc-43e4-bec7-42beb94ac219" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_d8199cd0-b1fc-417f-a203-ae310899b32e" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_SegmentReportingInformationLineItems_2810385f-b672-4b02-903f-1ce4549aae9a" xlink:to="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_d8199cd0-b1fc-417f-a203-ae310899b32e" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsAxis_2aabec01-ff6c-4bd1-861a-55c091636304" xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_ConsolidationItemsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_d8199cd0-b1fc-417f-a203-ae310899b32e" xlink:to="loc_srt_ConsolidationItemsAxis_2aabec01-ff6c-4bd1-861a-55c091636304" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_2aabec01-ff6c-4bd1-861a-55c091636304_default" xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_ConsolidationItemsAxis_2aabec01-ff6c-4bd1-861a-55c091636304" xlink:to="loc_srt_ConsolidationItemsDomain_2aabec01-ff6c-4bd1-861a-55c091636304_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ConsolidationItemsDomain_55af0bfe-242b-434b-ab85-494ac76e395d" xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_ConsolidationItemsDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_ConsolidationItemsAxis_2aabec01-ff6c-4bd1-861a-55c091636304" xlink:to="loc_srt_ConsolidationItemsDomain_55af0bfe-242b-434b-ab85-494ac76e395d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OperatingSegmentsMember_2d9c0ff3-9287-4d52-aa39-674f7972d4b1" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_OperatingSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_55af0bfe-242b-434b-ab85-494ac76e395d" xlink:to="loc_us-gaap_OperatingSegmentsMember_2d9c0ff3-9287-4d52-aa39-674f7972d4b1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_IntersegmentEliminationMember_0bf87ccd-29f5-4d31-a766-29b800cc581f" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_IntersegmentEliminationMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ConsolidationItemsDomain_55af0bfe-242b-434b-ab85-494ac76e395d" xlink:to="loc_us-gaap_IntersegmentEliminationMember_0bf87ccd-29f5-4d31-a766-29b800cc581f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_35492289-8035-4450-a740-7e5885e1faa0" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_d8199cd0-b1fc-417f-a203-ae310899b32e" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_35492289-8035-4450-a740-7e5885e1faa0" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_35492289-8035-4450-a740-7e5885e1faa0_default" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_35492289-8035-4450-a740-7e5885e1faa0" xlink:to="loc_us-gaap_SegmentDomain_35492289-8035-4450-a740-7e5885e1faa0_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_ea18d4ad-6019-4c61-b32e-200386351e38" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_35492289-8035-4450-a740-7e5885e1faa0" xlink:to="loc_us-gaap_SegmentDomain_ea18d4ad-6019-4c61-b32e-200386351e38" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_ElectricalInfrastructureMember_1ca6274f-1d12-4417-b93a-8df98d0e46fb" xlink:href="mtrx-20200630.xsd#mtrx_ElectricalInfrastructureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_ea18d4ad-6019-4c61-b32e-200386351e38" xlink:to="loc_mtrx_ElectricalInfrastructureMember_1ca6274f-1d12-4417-b93a-8df98d0e46fb" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_OilGasAndChemicalMember_95fa46ef-1b98-4e2f-96c7-77a1db1b5925" xlink:href="mtrx-20200630.xsd#mtrx_OilGasAndChemicalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_ea18d4ad-6019-4c61-b32e-200386351e38" xlink:to="loc_mtrx_OilGasAndChemicalMember_95fa46ef-1b98-4e2f-96c7-77a1db1b5925" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_StorageSolutionsMember_37eef06c-a570-4ec1-a96b-12e5e9199c82" xlink:href="mtrx-20200630.xsd#mtrx_StorageSolutionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_ea18d4ad-6019-4c61-b32e-200386351e38" xlink:to="loc_mtrx_StorageSolutionsMember_37eef06c-a570-4ec1-a96b-12e5e9199c82" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_IndustrialMember_c68c81fd-9f5f-40e6-a516-3d3918300b81" xlink:href="mtrx-20200630.xsd#mtrx_IndustrialMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_ea18d4ad-6019-4c61-b32e-200386351e38" xlink:to="loc_mtrx_IndustrialMember_c68c81fd-9f5f-40e6-a516-3d3918300b81" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllOtherSegmentsMember_6529d662-689c-443f-898a-c035218b07dc" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_AllOtherSegmentsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_ea18d4ad-6019-4c61-b32e-200386351e38" xlink:to="loc_us-gaap_AllOtherSegmentsMember_6529d662-689c-443f-898a-c035218b07dc" xlink:type="arc" order="4"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/SegmentInformationDetails1" xlink:type="simple" xlink:href="mtrx-20200630.xsd#SegmentInformationDetails1"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/SegmentInformationDetails1" xlink:type="extended" id="ib6a0f576db554657b4973fbf722ff61e_SegmentInformationDetails1">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems_fb3574c1-67aa-4400-9fe3-7207d96b8cb5" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_ScheduleOfSegmentReportingInformationByGeographicAreasAbstract_6971cebd-ff50-4d2b-8a7f-1474efa71f23" xlink:href="mtrx-20200630.xsd#mtrx_ScheduleOfSegmentReportingInformationByGeographicAreasAbstract"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems_fb3574c1-67aa-4400-9fe3-7207d96b8cb5" xlink:to="loc_mtrx_ScheduleOfSegmentReportingInformationByGeographicAreasAbstract_6971cebd-ff50-4d2b-8a7f-1474efa71f23" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_NoncurrentAssets_d9b170b0-67d7-4bdd-9ba2-f9a673bbc94d" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_NoncurrentAssets"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_mtrx_ScheduleOfSegmentReportingInformationByGeographicAreasAbstract_6971cebd-ff50-4d2b-8a7f-1474efa71f23" xlink:to="loc_us-gaap_NoncurrentAssets_d9b170b0-67d7-4bdd-9ba2-f9a673bbc94d" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable_06d75644-00c7-47be-a7c3-1170559658f6" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RevenuesFromExternalCustomersAndLongLivedAssetsLineItems_fb3574c1-67aa-4400-9fe3-7207d96b8cb5" xlink:to="loc_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable_06d75644-00c7-47be-a7c3-1170559658f6" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_StatementGeographicalAxis_5c506acb-80df-4e7a-8e0a-794d1247a80f" xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_StatementGeographicalAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRevenuesFromExternalCustomersAndLongLivedAssetsTable_06d75644-00c7-47be-a7c3-1170559658f6" xlink:to="loc_srt_StatementGeographicalAxis_5c506acb-80df-4e7a-8e0a-794d1247a80f" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_5c506acb-80df-4e7a-8e0a-794d1247a80f_default" xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_StatementGeographicalAxis_5c506acb-80df-4e7a-8e0a-794d1247a80f" xlink:to="loc_srt_SegmentGeographicalDomain_5c506acb-80df-4e7a-8e0a-794d1247a80f_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_SegmentGeographicalDomain_952aead5-8934-4793-ada3-ef40a553bb32" xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_SegmentGeographicalDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_StatementGeographicalAxis_5c506acb-80df-4e7a-8e0a-794d1247a80f" xlink:to="loc_srt_SegmentGeographicalDomain_952aead5-8934-4793-ada3-ef40a553bb32" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_US_8c70c8f7-a847-43cf-9fa9-15b908018f67" xlink:href="https://xbrl.sec.gov/country/2020/country-2020-01-31.xsd#country_US"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_952aead5-8934-4793-ada3-ef40a553bb32" xlink:to="loc_country_US_8c70c8f7-a847-43cf-9fa9-15b908018f67" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_country_CA_0a67e74b-8a13-40dc-b843-8735fb5866a1" xlink:href="https://xbrl.sec.gov/country/2020/country-2020-01-31.xsd#country_CA"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_952aead5-8934-4793-ada3-ef40a553bb32" xlink:to="loc_country_CA_0a67e74b-8a13-40dc-b843-8735fb5866a1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_InternationalMember_abe63c2c-e3a2-4202-9395-67a711e96dc6" xlink:href="mtrx-20200630.xsd#mtrx_InternationalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_SegmentGeographicalDomain_952aead5-8934-4793-ada3-ef40a553bb32" xlink:to="loc_mtrx_InternationalMember_abe63c2c-e3a2-4202-9395-67a711e96dc6" xlink:type="arc" order="2"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/SegmentInformationDetails2" xlink:type="simple" xlink:href="mtrx-20200630.xsd#SegmentInformationDetails2"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/SegmentInformationDetails2" xlink:type="extended" id="ic8f005ef45074c1b980648cb09b17976_SegmentInformationDetails2">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_EntityWideRevenueMajorCustomerLineItems_70799910-344b-4b19-b613-1de39336a63e" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_EntityWideRevenueMajorCustomerLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ConcentrationRiskPercentage1_69e304b4-8a26-43c5-9065-986dcb046db6" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ConcentrationRiskPercentage1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_EntityWideRevenueMajorCustomerLineItems_70799910-344b-4b19-b613-1de39336a63e" xlink:to="loc_us-gaap_ConcentrationRiskPercentage1_69e304b4-8a26-43c5-9065-986dcb046db6" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfEntityWideRevenueByMajorCustomersByReportingSegmentsTable_d9a6268d-93ce-46fb-87d9-0b6d2167acc9" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ScheduleOfEntityWideRevenueByMajorCustomersByReportingSegmentsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_EntityWideRevenueMajorCustomerLineItems_70799910-344b-4b19-b613-1de39336a63e" xlink:to="loc_us-gaap_ScheduleOfEntityWideRevenueByMajorCustomersByReportingSegmentsTable_d9a6268d-93ce-46fb-87d9-0b6d2167acc9" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_64e7784b-a957-4692-8997-218c9642d8e6" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEntityWideRevenueByMajorCustomersByReportingSegmentsTable_d9a6268d-93ce-46fb-87d9-0b6d2167acc9" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_64e7784b-a957-4692-8997-218c9642d8e6" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_64e7784b-a957-4692-8997-218c9642d8e6_default" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_64e7784b-a957-4692-8997-218c9642d8e6" xlink:to="loc_us-gaap_SegmentDomain_64e7784b-a957-4692-8997-218c9642d8e6_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_0fb60ca2-098a-4073-869f-67a4857e55fc" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_64e7784b-a957-4692-8997-218c9642d8e6" xlink:to="loc_us-gaap_SegmentDomain_0fb60ca2-098a-4073-869f-67a4857e55fc" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_ElectricalInfrastructureMember_c7874235-b857-4428-b922-b94bd2a7279d" xlink:href="mtrx-20200630.xsd#mtrx_ElectricalInfrastructureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_0fb60ca2-098a-4073-869f-67a4857e55fc" xlink:to="loc_mtrx_ElectricalInfrastructureMember_c7874235-b857-4428-b922-b94bd2a7279d" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_OilGasAndChemicalMember_4b0384b8-5133-4c42-8ae0-d99f37acd1c1" xlink:href="mtrx-20200630.xsd#mtrx_OilGasAndChemicalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_0fb60ca2-098a-4073-869f-67a4857e55fc" xlink:to="loc_mtrx_OilGasAndChemicalMember_4b0384b8-5133-4c42-8ae0-d99f37acd1c1" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_StorageSolutionsMember_064476cb-3cda-48c2-85f6-1fe28fa29b95" xlink:href="mtrx-20200630.xsd#mtrx_StorageSolutionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_0fb60ca2-098a-4073-869f-67a4857e55fc" xlink:to="loc_mtrx_StorageSolutionsMember_064476cb-3cda-48c2-85f6-1fe28fa29b95" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_IndustrialMember_b7db08c2-3659-48b4-9f40-f90d43be35e0" xlink:href="mtrx-20200630.xsd#mtrx_IndustrialMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_0fb60ca2-098a-4073-869f-67a4857e55fc" xlink:to="loc_mtrx_IndustrialMember_b7db08c2-3659-48b4-9f40-f90d43be35e0" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_MajorCustomersAxis_25becd16-62a4-406c-b4d2-df62a0c9a516" xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_MajorCustomersAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfEntityWideRevenueByMajorCustomersByReportingSegmentsTable_d9a6268d-93ce-46fb-87d9-0b6d2167acc9" xlink:to="loc_srt_MajorCustomersAxis_25becd16-62a4-406c-b4d2-df62a0c9a516" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_NameOfMajorCustomerDomain_25becd16-62a4-406c-b4d2-df62a0c9a516_default" xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_NameOfMajorCustomerDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_srt_MajorCustomersAxis_25becd16-62a4-406c-b4d2-df62a0c9a516" xlink:to="loc_srt_NameOfMajorCustomerDomain_25becd16-62a4-406c-b4d2-df62a0c9a516_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_NameOfMajorCustomerDomain_ba42a196-abc1-4e32-8c9a-d78dad86ae32" xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_NameOfMajorCustomerDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_srt_MajorCustomersAxis_25becd16-62a4-406c-b4d2-df62a0c9a516" xlink:to="loc_srt_NameOfMajorCustomerDomain_ba42a196-abc1-4e32-8c9a-d78dad86ae32" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_CustomerOneMember_71401179-edb4-4766-befc-2a254c15d545" xlink:href="mtrx-20200630.xsd#mtrx_CustomerOneMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NameOfMajorCustomerDomain_ba42a196-abc1-4e32-8c9a-d78dad86ae32" xlink:to="loc_mtrx_CustomerOneMember_71401179-edb4-4766-befc-2a254c15d545" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_CustomerTwoMember_31d108b0-6b8a-41df-9382-9fcc263b3872" xlink:href="mtrx-20200630.xsd#mtrx_CustomerTwoMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NameOfMajorCustomerDomain_ba42a196-abc1-4e32-8c9a-d78dad86ae32" xlink:to="loc_mtrx_CustomerTwoMember_31d108b0-6b8a-41df-9382-9fcc263b3872" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_CustomerThreeMember_23616390-9dd8-4ba7-9746-c33d7f3fe957" xlink:href="mtrx-20200630.xsd#mtrx_CustomerThreeMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NameOfMajorCustomerDomain_ba42a196-abc1-4e32-8c9a-d78dad86ae32" xlink:to="loc_mtrx_CustomerThreeMember_23616390-9dd8-4ba7-9746-c33d7f3fe957" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_CustomerFourMember_aa3a2bfd-8866-4847-ac0b-4373eebafca9" xlink:href="mtrx-20200630.xsd#mtrx_CustomerFourMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NameOfMajorCustomerDomain_ba42a196-abc1-4e32-8c9a-d78dad86ae32" xlink:to="loc_mtrx_CustomerFourMember_aa3a2bfd-8866-4847-ac0b-4373eebafca9" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_CustomerFiveMemberMember_b1ce1fe1-10f7-4017-a4a4-20bf16d31127" xlink:href="mtrx-20200630.xsd#mtrx_CustomerFiveMemberMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NameOfMajorCustomerDomain_ba42a196-abc1-4e32-8c9a-d78dad86ae32" xlink:to="loc_mtrx_CustomerFiveMemberMember_b1ce1fe1-10f7-4017-a4a4-20bf16d31127" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_CustomerSixMember_e61957a3-29ae-4146-8db8-d8ae3781a23c" xlink:href="mtrx-20200630.xsd#mtrx_CustomerSixMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NameOfMajorCustomerDomain_ba42a196-abc1-4e32-8c9a-d78dad86ae32" xlink:to="loc_mtrx_CustomerSixMember_e61957a3-29ae-4146-8db8-d8ae3781a23c" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_CustomerSevenMember_24c6ca13-4bd1-4b4d-b424-0d12a2a4c5f2" xlink:href="mtrx-20200630.xsd#mtrx_CustomerSevenMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NameOfMajorCustomerDomain_ba42a196-abc1-4e32-8c9a-d78dad86ae32" xlink:to="loc_mtrx_CustomerSevenMember_24c6ca13-4bd1-4b4d-b424-0d12a2a4c5f2" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_CustomerEightMember_074c8372-d758-43c3-a585-d64cb4fc3a13" xlink:href="mtrx-20200630.xsd#mtrx_CustomerEightMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NameOfMajorCustomerDomain_ba42a196-abc1-4e32-8c9a-d78dad86ae32" xlink:to="loc_mtrx_CustomerEightMember_074c8372-d758-43c3-a585-d64cb4fc3a13" xlink:type="arc" order="7"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_CustomerNineMember_7e9251ca-d9c5-48eb-a79e-8c2cca51b2ed" xlink:href="mtrx-20200630.xsd#mtrx_CustomerNineMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NameOfMajorCustomerDomain_ba42a196-abc1-4e32-8c9a-d78dad86ae32" xlink:to="loc_mtrx_CustomerNineMember_7e9251ca-d9c5-48eb-a79e-8c2cca51b2ed" xlink:type="arc" order="8"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_CustomerTenMember_4d3938fe-331e-4b7f-81b5-effa8d28abfe" xlink:href="mtrx-20200630.xsd#mtrx_CustomerTenMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NameOfMajorCustomerDomain_ba42a196-abc1-4e32-8c9a-d78dad86ae32" xlink:to="loc_mtrx_CustomerTenMember_4d3938fe-331e-4b7f-81b5-effa8d28abfe" xlink:type="arc" order="9"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_CustomerElevenMember_d89bc504-0e78-41d6-ba0d-657e58f76b2b" xlink:href="mtrx-20200630.xsd#mtrx_CustomerElevenMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NameOfMajorCustomerDomain_ba42a196-abc1-4e32-8c9a-d78dad86ae32" xlink:to="loc_mtrx_CustomerElevenMember_d89bc504-0e78-41d6-ba0d-657e58f76b2b" xlink:type="arc" order="10"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_CustomerTwelveMember_52072b52-c676-4aed-9790-44d409cf7c6a" xlink:href="mtrx-20200630.xsd#mtrx_CustomerTwelveMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NameOfMajorCustomerDomain_ba42a196-abc1-4e32-8c9a-d78dad86ae32" xlink:to="loc_mtrx_CustomerTwelveMember_52072b52-c676-4aed-9790-44d409cf7c6a" xlink:type="arc" order="11"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_CustomerThirteenMember_1b222837-5d54-4521-bf4a-967bb153511c" xlink:href="mtrx-20200630.xsd#mtrx_CustomerThirteenMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_NameOfMajorCustomerDomain_ba42a196-abc1-4e32-8c9a-d78dad86ae32" xlink:to="loc_mtrx_CustomerThirteenMember_1b222837-5d54-4521-bf4a-967bb153511c" xlink:type="arc" order="12"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/RestructuringCosts" xlink:type="simple" xlink:href="mtrx-20200630.xsd#RestructuringCosts"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/RestructuringCosts" xlink:type="extended" id="ic2c1ca2dde1647d0b89131636ab7fcbb_RestructuringCosts"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/RestructuringCostsTables" xlink:type="simple" xlink:href="mtrx-20200630.xsd#RestructuringCostsTables"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/RestructuringCostsTables" xlink:type="extended" id="i9954be1fbce84c7a9e2df46868b2afd6_RestructuringCostsTables"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/RestructuringCostsDetails" xlink:type="simple" xlink:href="mtrx-20200630.xsd#RestructuringCostsDetails"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/RestructuringCostsDetails" xlink:type="extended" id="i119ad0b9e3b545e48a7955b571eb56e6_RestructuringCostsDetails">
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringCostAndReserveLineItems_ac85e18f-d246-4b5c-9491-276019dbf4c8" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_RestructuringCostAndReserveLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SeveranceCosts1_075ae91d-2534-4269-a9d5-14405086d6ed" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_SeveranceCosts1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_ac85e18f-d246-4b5c-9491-276019dbf4c8" xlink:to="loc_us-gaap_SeveranceCosts1_075ae91d-2534-4269-a9d5-14405086d6ed" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_BusinessExitCosts1_79af47dd-3e56-451e-bf41-a24cee04c69e" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_BusinessExitCosts1"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_ac85e18f-d246-4b5c-9491-276019dbf4c8" xlink:to="loc_us-gaap_BusinessExitCosts1_79af47dd-3e56-451e-bf41-a24cee04c69e" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ImpairmentOfIntangibleAssetsIndefinitelivedExcludingGoodwill_11e51d50-5fb1-4114-b0b4-15af4a091264" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ImpairmentOfIntangibleAssetsIndefinitelivedExcludingGoodwill"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_ac85e18f-d246-4b5c-9491-276019dbf4c8" xlink:to="loc_us-gaap_ImpairmentOfIntangibleAssetsIndefinitelivedExcludingGoodwill_11e51d50-5fb1-4114-b0b4-15af4a091264" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringReserve_af9c01ac-1156-4405-aec3-3612eb393067" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_RestructuringReserve"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_ac85e18f-d246-4b5c-9491-276019dbf4c8" xlink:to="loc_us-gaap_RestructuringReserve_af9c01ac-1156-4405-aec3-3612eb393067" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_RestructuringCharges_7470f919-840e-4a6a-a51e-66b33b2c6817" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_RestructuringCharges"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_ac85e18f-d246-4b5c-9491-276019dbf4c8" xlink:to="loc_us-gaap_RestructuringCharges_7470f919-840e-4a6a-a51e-66b33b2c6817" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_OtherAssetImpairmentCharges_8fbdc543-2a87-4174-a756-c5e46203c69d" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_OtherAssetImpairmentCharges"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_ac85e18f-d246-4b5c-9491-276019dbf4c8" xlink:to="loc_us-gaap_OtherAssetImpairmentCharges_8fbdc543-2a87-4174-a756-c5e46203c69d" xlink:type="arc" order="5"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_PaymentsForRestructuring_3145cffe-32e8-465e-ab59-da3b01652dfb" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_PaymentsForRestructuring"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_ac85e18f-d246-4b5c-9491-276019dbf4c8" xlink:to="loc_us-gaap_PaymentsForRestructuring_3145cffe-32e8-465e-ab59-da3b01652dfb" xlink:type="arc" order="6"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_712e6e6d-e1db-40b1-9f61-95e0c94be3e3" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ScheduleOfRestructuringAndRelatedCostsTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_us-gaap_RestructuringCostAndReserveLineItems_ac85e18f-d246-4b5c-9491-276019dbf4c8" xlink:to="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_712e6e6d-e1db-40b1-9f61-95e0c94be3e3" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_StatementBusinessSegmentsAxis_ace70ba6-a2af-416e-8da3-fe1724ea02d7" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_StatementBusinessSegmentsAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_us-gaap_ScheduleOfRestructuringAndRelatedCostsTable_712e6e6d-e1db-40b1-9f61-95e0c94be3e3" xlink:to="loc_us-gaap_StatementBusinessSegmentsAxis_ace70ba6-a2af-416e-8da3-fe1724ea02d7" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_ace70ba6-a2af-416e-8da3-fe1724ea02d7_default" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_ace70ba6-a2af-416e-8da3-fe1724ea02d7" xlink:to="loc_us-gaap_SegmentDomain_ace70ba6-a2af-416e-8da3-fe1724ea02d7_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_SegmentDomain_cf2537dc-1f5f-4450-8156-7bdc5ece3102" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_SegmentDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_StatementBusinessSegmentsAxis_ace70ba6-a2af-416e-8da3-fe1724ea02d7" xlink:to="loc_us-gaap_SegmentDomain_cf2537dc-1f5f-4450-8156-7bdc5ece3102" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_ElectricalInfrastructureMember_c9dfeb32-38a2-476b-b4dc-40eb1d2b8175" xlink:href="mtrx-20200630.xsd#mtrx_ElectricalInfrastructureMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_cf2537dc-1f5f-4450-8156-7bdc5ece3102" xlink:to="loc_mtrx_ElectricalInfrastructureMember_c9dfeb32-38a2-476b-b4dc-40eb1d2b8175" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_OilGasAndChemicalMember_24d07df6-026e-4caf-9683-2e2fa9646e95" xlink:href="mtrx-20200630.xsd#mtrx_OilGasAndChemicalMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_cf2537dc-1f5f-4450-8156-7bdc5ece3102" xlink:to="loc_mtrx_OilGasAndChemicalMember_24d07df6-026e-4caf-9683-2e2fa9646e95" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_StorageSolutionsMember_4b9e21f3-94e7-4482-bce6-c8f4740c4c61" xlink:href="mtrx-20200630.xsd#mtrx_StorageSolutionsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_cf2537dc-1f5f-4450-8156-7bdc5ece3102" xlink:to="loc_mtrx_StorageSolutionsMember_4b9e21f3-94e7-4482-bce6-c8f4740c4c61" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_mtrx_IndustrialMember_b2ea596b-f083-4eef-a8f8-5c57f3272525" xlink:href="mtrx-20200630.xsd#mtrx_IndustrialMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_SegmentDomain_cf2537dc-1f5f-4450-8156-7bdc5ece3102" xlink:to="loc_mtrx_IndustrialMember_b2ea596b-f083-4eef-a8f8-5c57f3272525" xlink:type="arc" order="3"/>
  </link:definitionLink>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/QuarterlyFinancialDataUnauditedQuarterlyFinancialDataUnaudited" xlink:type="simple" xlink:href="mtrx-20200630.xsd#QuarterlyFinancialDataUnauditedQuarterlyFinancialDataUnaudited"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/QuarterlyFinancialDataUnauditedQuarterlyFinancialDataUnaudited" xlink:type="extended" id="ieb7d4a0ef8c04591b4e6e675f780ed8d_QuarterlyFinancialDataUnauditedQuarterlyFinancialDataUnaudited"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/QuarterlyFinancialDataUnauditedTables" xlink:type="simple" xlink:href="mtrx-20200630.xsd#QuarterlyFinancialDataUnauditedTables"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/QuarterlyFinancialDataUnauditedTables" xlink:type="extended" id="i59a79d6bf28c468d8022ce6a6ffe0167_QuarterlyFinancialDataUnauditedTables"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/QuarterlyFinancialDataUnauditedDetails" xlink:type="simple" xlink:href="mtrx-20200630.xsd#QuarterlyFinancialDataUnauditedDetails"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/QuarterlyFinancialDataUnauditedDetails" xlink:type="extended" id="i5c8bdc86e28e4a5e8ff874fab3ad27d9_QuarterlyFinancialDataUnauditedDetails"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/ValuationandQualifyingAccounts" xlink:type="simple" xlink:href="mtrx-20200630.xsd#ValuationandQualifyingAccounts"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/ValuationandQualifyingAccounts" xlink:type="extended" id="i166759cc16aa440f873eb8967070edd5_ValuationandQualifyingAccounts"/>
  <link:roleRef roleURI="http://www.matrixservicecompany.com/role/ValuationandQualifyingAccountsDetails" xlink:type="simple" xlink:href="mtrx-20200630.xsd#ValuationandQualifyingAccountsDetails"/>
  <link:definitionLink xlink:role="http://www.matrixservicecompany.com/role/ValuationandQualifyingAccountsDetails" xlink:type="extended" id="iaf90315732964340be49e64ad9239506_ValuationandQualifyingAccountsDetails">
    <link:loc xlink:type="locator" xlink:label="loc_srt_ValuationAndQualifyingAccountsDisclosureLineItems_9e0e82ba-6135-4752-a02c-789f8da3247e" xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_ValuationAndQualifyingAccountsDisclosureLineItems"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_MovementInValuationAllowancesAndReservesRollForward_0f366c95-43b5-49cd-bdc9-eec742b9a399" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_MovementInValuationAllowancesAndReservesRollForward"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_srt_ValuationAndQualifyingAccountsDisclosureLineItems_9e0e82ba-6135-4752-a02c-789f8da3247e" xlink:to="loc_us-gaap_MovementInValuationAllowancesAndReservesRollForward_0f366c95-43b5-49cd-bdc9-eec742b9a399" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationAllowancesAndReservesBalance_d53b9543-6fca-45d5-a798-495260d45bee" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ValuationAllowancesAndReservesBalance"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MovementInValuationAllowancesAndReservesRollForward_0f366c95-43b5-49cd-bdc9-eec742b9a399" xlink:to="loc_us-gaap_ValuationAllowancesAndReservesBalance_d53b9543-6fca-45d5-a798-495260d45bee" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationAllowancesAndReservesChargedToCostAndExpense_3424fa43-d309-47af-a8c4-3500a767dd8a" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ValuationAllowancesAndReservesChargedToCostAndExpense"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MovementInValuationAllowancesAndReservesRollForward_0f366c95-43b5-49cd-bdc9-eec742b9a399" xlink:to="loc_us-gaap_ValuationAllowancesAndReservesChargedToCostAndExpense_3424fa43-d309-47af-a8c4-3500a767dd8a" xlink:type="arc" order="2"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationAllowancesAndReservesChargedToOtherAccounts_dade8f50-784f-40c9-9de2-f12b48a5d888" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ValuationAllowancesAndReservesChargedToOtherAccounts"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MovementInValuationAllowancesAndReservesRollForward_0f366c95-43b5-49cd-bdc9-eec742b9a399" xlink:to="loc_us-gaap_ValuationAllowancesAndReservesChargedToOtherAccounts_dade8f50-784f-40c9-9de2-f12b48a5d888" xlink:type="arc" order="3"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationAllowancesAndReservesDeductions_0dbff3e7-0707-4eea-bd39-59dcce0e150b" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ValuationAllowancesAndReservesDeductions"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_MovementInValuationAllowancesAndReservesRollForward_0f366c95-43b5-49cd-bdc9-eec742b9a399" xlink:to="loc_us-gaap_ValuationAllowancesAndReservesDeductions_0dbff3e7-0707-4eea-bd39-59dcce0e150b" xlink:type="arc" order="4"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationAllowancesAndReservesBalance_a02fed98-6cd8-4a45-9205-4dc530cd8f85" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ValuationAllowancesAndReservesBalance"/>
    <link:loc xlink:type="locator" xlink:label="loc_srt_ValuationAndQualifyingAccountsDisclosureTable_26cb6233-a88d-4015-861b-3c67177c7e11" xlink:href="http://xbrl.fasb.org/srt/2020/elts/srt-2020-01-31.xsd#srt_ValuationAndQualifyingAccountsDisclosureTable"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/all" xlink:from="loc_srt_ValuationAndQualifyingAccountsDisclosureLineItems_9e0e82ba-6135-4752-a02c-789f8da3247e" xlink:to="loc_srt_ValuationAndQualifyingAccountsDisclosureTable_26cb6233-a88d-4015-861b-3c67177c7e11" xlink:type="arc" order="1" xbrldt:closed="true" xbrldt:contextElement="segment"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationAllowancesAndReservesTypeAxis_c018e1e6-e361-4255-8e66-691e7d976532" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ValuationAllowancesAndReservesTypeAxis"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/hypercube-dimension" xlink:from="loc_srt_ValuationAndQualifyingAccountsDisclosureTable_26cb6233-a88d-4015-861b-3c67177c7e11" xlink:to="loc_us-gaap_ValuationAllowancesAndReservesTypeAxis_c018e1e6-e361-4255-8e66-691e7d976532" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationAllowancesAndReservesDomain_c018e1e6-e361-4255-8e66-691e7d976532_default" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ValuationAllowancesAndReservesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-default" xlink:from="loc_us-gaap_ValuationAllowancesAndReservesTypeAxis_c018e1e6-e361-4255-8e66-691e7d976532" xlink:to="loc_us-gaap_ValuationAllowancesAndReservesDomain_c018e1e6-e361-4255-8e66-691e7d976532_default" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationAllowancesAndReservesDomain_5b6bf315-e042-4a39-8a21-f9bafb2b9d51" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ValuationAllowancesAndReservesDomain"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/dimension-domain" xlink:from="loc_us-gaap_ValuationAllowancesAndReservesTypeAxis_c018e1e6-e361-4255-8e66-691e7d976532" xlink:to="loc_us-gaap_ValuationAllowancesAndReservesDomain_5b6bf315-e042-4a39-8a21-f9bafb2b9d51" xlink:type="arc" order="1"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_AllowanceForCreditLossMember_da00af9a-a719-4d9e-a191-1eee737090b1" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_AllowanceForCreditLossMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ValuationAllowancesAndReservesDomain_5b6bf315-e042-4a39-8a21-f9bafb2b9d51" xlink:to="loc_us-gaap_AllowanceForCreditLossMember_da00af9a-a719-4d9e-a191-1eee737090b1" xlink:type="arc" order="0"/>
    <link:loc xlink:type="locator" xlink:label="loc_us-gaap_ValuationAllowanceOfDeferredTaxAssetsMember_901f85a7-ddaa-451e-b303-e2ce0f8a677d" xlink:href="http://xbrl.fasb.org/us-gaap/2020/elts/us-gaap-2020-01-31.xsd#us-gaap_ValuationAllowanceOfDeferredTaxAssetsMember"/>
    <link:definitionArc xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="loc_us-gaap_ValuationAllowancesAndReservesDomain_5b6bf315-e042-4a39-8a21-f9bafb2b9d51" xlink:to="loc_us-gaap_ValuationAllowanceOfDeferredTaxAssetsMember_901f85a7-ddaa-451e-b303-e2ce0f8a677d" xlink:type="arc" order="1"/>
  </link:definitionLink>
</link:linkbase>
