-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
 MFgwCgYEVQgBAQICAf8DSgAwRwJAW2sNKK9AVtBzYZmr6aGjlWyK3XmZv3dTINen
 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 JeVGth4iO87gkaxlMkNWNyI3y9War2TqBNQSJdL1eapMQZMN98Z3togIK24wfi+y
 otsQ8PITeYn4vQ8q6lELEA==

<SEC-DOCUMENT>0001349477-06-000001.txt : 20060118
<SEC-HEADER>0001349477-06-000001.hdr.sgml : 20060118
<ACCEPTANCE-DATETIME>20060118152626
ACCESSION NUMBER:		0001349477-06-000001
CONFORMED SUBMISSION TYPE:	3
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20060116
FILED AS OF DATE:		20060118
DATE AS OF CHANGE:		20060118

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Pool Tana L
		CENTRAL INDEX KEY:			0001349477

	FILING VALUES:
		FORM TYPE:		3
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-13831
		FILM NUMBER:		06535494

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		713 985-6479

	MAIL ADDRESS:	
		STREET 1:		1360 POST OAK BLVD., SUITE 2100
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77056

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			QUANTA SERVICES INC
		CENTRAL INDEX KEY:			0001050915
		STANDARD INDUSTRIAL CLASSIFICATION:	ELECTRICAL WORK [1731]
		IRS NUMBER:				742851603
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		1360 POST OAK BLVD
		STREET 2:		SUITE 2100
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77056
		BUSINESS PHONE:		7133506000

	MAIL ADDRESS:	
		STREET 1:		1360 POST OAK BLVD SUITE 2100
		CITY:			HOUSTON
		STATE:			TX
		ZIP:			77056
</SEC-HEADER>
<DOCUMENT>
<TYPE>3
<SEQUENCE>1
<FILENAME>doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2006-01-16</periodOfReport>

    <noSecuritiesOwned>1</noSecuritiesOwned>

    <issuer>
        <issuerCik>0001050915</issuerCik>
        <issuerName>QUANTA SERVICES INC</issuerName>
        <issuerTradingSymbol>PWR</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001349477</rptOwnerCik>
            <rptOwnerName>Pool Tana L</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1360 POST OAK BLVD., SUITE 2100</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>HOUSTON</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>77056</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>VP and General Counsel</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <footnotes></footnotes>

    <ownerSignature>
        <signatureName>Vincent A. Mercaldi, Atty in Fact</signatureName>
        <signatureDate>2006-01-18</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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