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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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<SEC-DOCUMENT>0001179110-10-006138.txt : 20100330
<SEC-HEADER>0001179110-10-006138.hdr.sgml : 20100330
<ACCEPTANCE-DATETIME>20100330145314
ACCESSION NUMBER:		0001179110-10-006138
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20100329
FILED AS OF DATE:		20100330
DATE AS OF CHANGE:		20100330

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Theeuwes Alfons
		CENTRAL INDEX KEY:			0001440793

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-34145
		FILM NUMBER:		10713439

	MAIL ADDRESS:	
		STREET 1:		26000 COMMERCENTRE DR.
		CITY:			LAKE FOREST
		STATE:			CA
		ZIP:			92630

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Primoris Services CORP
		CENTRAL INDEX KEY:			0001361538
		STANDARD INDUSTRIAL CLASSIFICATION:	WATER, SEWER, PIPELINE, COMM AND POWER LINE CONSTRUCTION [1623]
		IRS NUMBER:				204743916
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		26000 COMMERCENTRE DRIVE
		CITY:			LAKE FOREST
		STATE:			CA
		ZIP:			92630
		BUSINESS PHONE:		(949) 598-9242

	MAIL ADDRESS:	
		STREET 1:		26000 COMMERCENTRE DRIVE
		CITY:			LAKE FOREST
		STATE:			CA
		ZIP:			92630

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	Rhapsody Acquisition Corp.
		DATE OF NAME CHANGE:	20060503
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>FORM 4 -
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2010-03-29</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001361538</issuerCik>
        <issuerName>Primoris Services CORP</issuerName>
        <issuerTradingSymbol>PRIM</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001440793</rptOwnerCik>
            <rptOwnerName>Theeuwes Alfons</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O PRIMORIS SERVICES CORPORATION</rptOwnerStreet1>
            <rptOwnerStreet2>26000 COMMERCENTRE DRIVE</rptOwnerStreet2>
            <rptOwnerCity>LAKE FOREST</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>92630</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Sr. VP of Acct. &amp; Finance</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-03-29</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>36419</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>272638</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By trust</value>
                    <footnoteId id="F2"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Shares issued through attaintment of 2009 EBITDA target per Merger Agreement filed on Form S-4A, and declared effective July 10, 2008.</footnote>
        <footnote id="F2">Shares held directy by Alfons Theeuwes Family Trust dated October 8, 2009 and indirectly by Alfons Theeuwes, as trustee of the trust.  The number of shares held by the trust are after settlement of a divorce decree relating to the transfer of 151,200 shares.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Peter J. Moerbeek, by power of attorney</signatureName>
        <signatureDate>2010-03-30</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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