<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0304</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2011-10-05</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000068270</issuerCik>
        <issuerName>RUBY TUESDAY INC</issuerName>
        <issuerTradingSymbol>RT</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001349005</rptOwnerCik>
            <rptOwnerName>Becker Steven R</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>300 CRESCENT COURT</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 1111</rptOwnerStreet2>
            <rptOwnerCity>DALLAS</rptOwnerCity>
            <rptOwnerState>TX</rptOwnerState>
            <rptOwnerZipCode>75201</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2011-10-05</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>10974</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>10974</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1031900</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Footnotes</value>
                    <footnoteId id="F2"/>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Represents grant of restricted stock award of 10,974 shares of common stock, par value $0.01 per share (&quot;Common Stock&quot;), of Ruby Tuesday, Inc. (the &quot;Issuer&quot;) to Steven R. Becker (&quot;Mr. Becker&quot;) under the Issuer's Stock Incentive and Deferred Compensation Plan for Directors.  Such shares are subject to forfeiture to the Issuer under certain circumstances, which forfeiture right will lapse on the earlier of October 4, 2012 and certain other events.</footnote>
        <footnote id="F2">Represents Common Stock of the Issuer directly beneficially owned by BD Partners III, L.P. (&quot;BD Partners III&quot;) (112,200 shares), Becker Drapkin Partners (QP), L.P. (&quot;Becker Drapkin QP&quot;) (416,801 shares), Becker Drapkin Partners, L.P. (&quot;Becker Drapkin, L.P.&quot;) (65,999 shares) and a managed account (the &quot;Managed Account&quot;) (436,900 shares). (continued in Footnote 3)</footnote>
        <footnote id="F3">Mr. Becker may be deemed to beneficially own such Common Stock as he is a co-managing member of BC Advisors, LLC, which is the general partner of BD Management (of which Mr. Becker is a limited partner), and BD Management is the general partner of, and investment manager for, each of BD Partners III, Becker Drapkin QP and Becker Drapkin, L.P. and provides investment advisory services for the Managed Account.  Mr. Becker disclaims beneficial ownership in such Common Stock except to the extent of his pecuniary interest therein.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Andrew S. McLelland, attorney-in-fact</signatureName>
        <signatureDate>2011-10-06</signatureDate>
    </ownerSignature>
</ownershipDocument>
