<?xml version="1.0" encoding="us-ascii"?>
<!--XBRL document created with Bowne Tagger. XBRL Parser version 10.0.0.34-->
<!--Based on XBRL 2.1-->
<!--Created on: 5/23/2009 3:52:46 PM-->
<!--Modified on: 3/1/2010 10:37:33 AM-->
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  <annotation>
    <appinfo>
      <link:roleType roleURI="http://quantaservices.com/role/DiscontinuedOperation" id="DiscontinuedOperation">
        <link:definition>0606 - Disclosure - Discontinued Operation</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://quantaservices.com/role/QuarterlyFinancialData" id="QuarterlyFinancialData">
        <link:definition>0617 - Disclosure - Quarterly Financial Data (Unaudited)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://quantaservices.com/role/RelatedPartyTransactions" id="RelatedPartyTransactions">
        <link:definition>0614 - Disclosure - Related Party Transactions</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://quantaservices.com/role/EmployeeBenefitPlans" id="EmployeeBenefitPlans">
        <link:definition>0613 - Disclosure - Employee Benefit Plans</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://quantaservices.com/role/LongTermIncentivePlans" id="LongTermIncentivePlans">
        <link:definition>0612 - Disclosure - Long-Term Incentive Plans</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://quantaservices.com/role/StockholdersEquity" id="StockholdersEquity">
        <link:definition>0611 - Disclosure - Equity</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://quantaservices.com/role/IncomeTaxes" id="IncomeTaxes">
        <link:definition>0610 - Disclosure - Income Taxes</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://quantaservices.com/role/DebtObligations" id="DebtObligations">
        <link:definition>0609 - Disclosure - Debt Obligations</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://quantaservices.com/role/DetailOfCertainBalanceSheetAccounts" id="DetailOfCertainBalanceSheetAccounts">
        <link:definition>0608 - Disclosure - Detail of Certain Balance Sheet Accounts</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://quantaservices.com/role/StatementsOfStockholdersEquity" id="StatementsOfStockholdersEquity">
        <link:definition>04 - Statement - Consolidated Statements of Shareholders' Equity</link:definition>
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        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://quantaservices.com/role/StatementsOfOperationsParenthetical" id="StatementsOfOperationsParenthetical">
        <link:definition>021 - Statement - Consolidated Statements of Operations (Parenthetical)</link:definition>
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        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://quantaservices.com/role/DocumentAndCompanyInformation" id="DocumentAndCompanyInformation">
        <link:definition>00 - Document - Document and Company Information</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://quantaservices.com/role/Acquistions" id="Acquistions">
        <link:definition>0604 - Disclosure - Acquisitions</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://quantaservices.com/role/ChangesInAccountingPrinciplesAndNewAccountingPronouncements" id="ChangesInAccountingPrinciplesAndNewAccountingPronouncements">
        <link:definition>0603 - Disclosure - Changes in Accounting Principles and New Accounting Pronouncements</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://quantaservices.com/role/SummaryOfSignificantAccountingPolicies" id="SummaryOfSignificantAccountingPolicies">
        <link:definition>0602 - Disclosure - Summary of Significant Accounting Policies</link:definition>
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        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://quantaservices.com/role/BalanceSheetsParenthetical" id="BalanceSheetsParenthetical">
        <link:definition>011 - Statement - Consolidated Balance Sheets (Parenthetical)</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://quantaservices.com/role/CommitmentsAndContingencies" id="CommitmentsAndContingencies">
        <link:definition>0615 - Disclosure - Commitments and Contingencies</link:definition>
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        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://quantaservices.com/role/SegmentInformation" id="SegmentInformation">
        <link:definition>0616 - Disclosure - Segment Information</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://quantaservices.com/role/PerShareInformation" id="PerShareInformation">
        <link:definition>0607 - Disclosure - Per Share Information</link:definition>
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        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://quantaservices.com/role/GoodwillAndOtherIntangibleAssets" id="GoodwillAndOtherIntangibleAssets">
        <link:definition>0605 - Disclosure - Goodwill and Other Intangible Assets</link:definition>
        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://quantaservices.com/role/BusinessAndOrganization" id="BusinessAndOrganization">
        <link:definition>0601 - Disclosure - Business and Organization</link:definition>
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        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://quantaservices.com/role/StatementsOfCashFlows" id="StatementsOfCashFlows">
        <link:definition>03 - Statement - Consolidated Statements of Cash Flows</link:definition>
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        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://quantaservices.com/role/StatementsOfOperations" id="StatementsOfOperations">
        <link:definition>02 - Statement - Consolidated Statements of Operations</link:definition>
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        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
      </link:roleType>
      <link:roleType roleURI="http://quantaservices.com/role/BalanceSheets" id="BalanceSheets">
        <link:definition>01 - Statement - Consolidated Balance Sheets</link:definition>
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        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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