<SEC-DOCUMENT>0001140361-11-037727.txt : 20110722
<SEC-HEADER>0001140361-11-037727.hdr.sgml : 20110722
<ACCEPTANCE-DATETIME>20110722132520
ACCESSION NUMBER:		0001140361-11-037727
CONFORMED SUBMISSION TYPE:	4/A
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20110719
FILED AS OF DATE:		20110722
DATE AS OF CHANGE:		20110722

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			DIFILLIPPO DAVID A
		CENTRAL INDEX KEY:			0001261137

	FILING VALUES:
		FORM TYPE:		4/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-08504
		FILM NUMBER:		11982142

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			UNIFIRST CORP
		CENTRAL INDEX KEY:			0000717954
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-PERSONAL SERVICES [7200]
		IRS NUMBER:				042103460
		STATE OF INCORPORATION:			MA
		FISCAL YEAR END:			0830

	BUSINESS ADDRESS:	
		STREET 1:		68 JONSPIN RD
		CITY:			WILMINGTON
		STATE:			MA
		ZIP:			01887
		BUSINESS PHONE:		(978) 658-8888

	MAIL ADDRESS:	
		STREET 1:		68 JONSPIN ROAD
		CITY:			WILMINGTON
		STATE:			MA
		ZIP:			01887

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	INTERSTATE UNIFORM SERVICES CORP/MA
		DATE OF NAME CHANGE:	19840410
</SEC-HEADER>
<DOCUMENT>
<TYPE>4/A
<SEQUENCE>1
<FILENAME>doc1.xml
<DESCRIPTION>FORM 4/A
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2011-07-19</periodOfReport>

    <dateOfOriginalSubmission>2011-07-21</dateOfOriginalSubmission>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000717954</issuerCik>
        <issuerName>UNIFIRST CORP</issuerName>
        <issuerTradingSymbol>UNF</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001261137</rptOwnerCik>
            <rptOwnerName>DIFILLIPPO DAVID A</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O UNIFIRST CORPORATION</rptOwnerStreet1>
            <rptOwnerStreet2>68 JONSPIN ROAD</rptOwnerStreet2>
            <rptOwnerCity>WILMINGTON</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>01887</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Senior VP of Operations</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>180</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                    <footnoteId id="F1"/>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By daughter</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>180</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                    <footnoteId id="F1"/>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By daughter</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>75</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                    <footnoteId id="F1"/>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By son</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3357</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F2"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Represents shares owned by David DiFillippo's children. David DiFillippo disclaims beneficial ownership of these reported securities, except to the extent of his pecuniary interest therein, and this report shall not be deemed an admission that he is the beneficial owner of these securities for purposes of Section 16 or any other purpose.</footnote>
        <footnote id="F2">On July 21, 2011, a Form 4 was inadvertently filed reporting a sale of 3,500 shares of UniFirst common stock on July 19, 2011 by Mr. DiFillippo.  Mr. DiFillippo did not sell any shares on July 19, 2011.  Accordingly, this Form 4/A is being filed to reflect that no shares were sold on July 19, 2011 and to reflect corrected information with respect to Mr. DiFillippo's direct ownership of UniFirst stock.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ David Whitman, Attorney-in-Fact</signatureName>
        <signatureDate>2011-07-22</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
