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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>0000866273-08-000010.txt : 20080521
<SEC-HEADER>0000866273-08-000010.hdr.sgml : 20080521
<ACCEPTANCE-DATETIME>20080521163302
ACCESSION NUMBER:		0000866273-08-000010
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20080519
FILED AS OF DATE:		20080521
DATE AS OF CHANGE:		20080521

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			MATRIX SERVICE CO
		CENTRAL INDEX KEY:			0000866273
		STANDARD INDUSTRIAL CLASSIFICATION:	CONSTRUCTION SPECIAL TRADE CONTRACTORS [1700]
		IRS NUMBER:				731352174
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0531

	BUSINESS ADDRESS:	
		STREET 1:		10701 E UTE ST
		CITY:			TULSA
		STATE:			OK
		ZIP:			74116-1517
		BUSINESS PHONE:		9188388822

	MAIL ADDRESS:	
		STREET 1:		10701 E UTE ST
		CITY:			TULSA
		STATE:			OK
		ZIP:			74116-1517

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Montalbano Joseph F
		CENTRAL INDEX KEY:			0001435427

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-15461
		FILM NUMBER:		08852187

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		(918) 838-9885

	MAIL ADDRESS:	
		STREET 1:		10701 E UTE ST
		CITY:			TULSA
		STATE:			OK
		ZIP:			74116
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2008-05-19</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000866273</issuerCik>
        <issuerName>MATRIX SERVICE CO</issuerName>
        <issuerTradingSymbol>MTRX</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001435427</rptOwnerCik>
            <rptOwnerName>Montalbano Joseph F</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>10701 E UTE ST</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>TULSA</rptOwnerCity>
            <rptOwnerState>OK</rptOwnerState>
            <rptOwnerZipCode>74116</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>VP / Chief Operating Officer</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
                <footnoteId id="F1"/>
            </securityTitle>
            <transactionDate>
                <value>2008-05-19</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>33175</value>
                    <footnoteId id="F2"/>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F3"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>33175</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Matrix Service Company Common Stock</footnote>
        <footnote id="F2">Restricted Stock Unit - each unit will entitle the reporting person to one share of Matrix Service Company Common Stock if and when the conditions of the restrictions have been satisfied.  For this grant, 50% will vest after completion of one year of employment and the remainder will vest in equal installments over the subsequent four year period.</footnote>
        <footnote id="F3">Not applicable</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Joseph F Montalbano</signatureName>
        <signatureDate>2008-05-21</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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