<SEC-DOCUMENT>0001209191-20-056168.txt : 20201028
<SEC-HEADER>0001209191-20-056168.hdr.sgml : 20201028
<ACCEPTANCE-DATETIME>20201028214808
ACCESSION NUMBER:		0001209191-20-056168
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20201026
FILED AS OF DATE:		20201028
DATE AS OF CHANGE:		20201028

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Cohen Phillip L
		CENTRAL INDEX KEY:			0001303645

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-08504
		FILM NUMBER:		201270264

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

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:			0829

	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
<SEQUENCE>1
<FILENAME>doc4.xml
<DESCRIPTION>FORM 4 SUBMISSION
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2020-10-26</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001303645</rptOwnerCik>
            <rptOwnerName>Cohen Phillip L</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O UNIFIRST CORP</rptOwnerStreet1>
            <rptOwnerStreet2>68 JONSPIN ROAD</rptOwnerStreet2>
            <rptOwnerCity>WILMINGTON</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>01887</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Appreciation Right</value>
                <footnoteId id="F1"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>166.94</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2020-10-26</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2020-10-26</value>
            </exerciseDate>
            <expirationDate>
                <value>2028-10-26</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock ($0.10 par value)</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>1000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">This stock appreciation right is exercisable in full on the grant date (10/26/2020) and is required to be settled in stock at the time of exercise. The grant has an expiration date of the earlier of October 26, 2028 or the second anniversary of the date that the grantee ceases to be a member of the Board of Directors.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Steven S. Sintros, Attorney-in-Fact</signatureName>
        <signatureDate>2020-10-28</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
