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

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2010-10-08</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001017712</issuerCik>
        <issuerName>HOT TOPIC INC /CA/</issuerName>
        <issuerTradingSymbol>HOTT</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>2010-10-08</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>2819</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2819</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2385949</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 2,819 shares of common stock (&quot;Common Stock&quot;), no par value, of Hot Topic, Inc. (the &quot;Issuer&quot;) granted to Steven R. Becker (&quot;Mr. Becker&quot;) as restricted stock under the Issuer's 2006 Equity Incentive Plan.  Pursuant to the Restricted Stock Bonus Agreement under which this grant was made, such shares are subject to forfeiture to the Issuer under certain circumstances, which forfeiture right will lapse on June 8, 2011, or the date of the next annual shareholders meeting of the Issuer, whichever comes first.</footnote>
        <footnote id="F2">Represents shares of Common Stock directly beneficially owned by BD Partners I, L.P. (&quot;BD Partners I&quot;) (827,953 shares), Becker Drapkin Partners (QP), L.P. (&quot;Becker Drapkin QP&quot;) (701,852 shares), Becker Drapkin Partners, L.P. (&quot;Becker Drapkin, L.P.&quot;) (86,744 shares), and a managed account (the &quot;Managed Account&quot;) (769,400 shares). (continued in Footnote 3)</footnote>
        <footnote id="F3">Mr. Becker may be deemed to beneficially own these shares as he is a co-managing member of BC Advisors, LLC which is the general partner of BD Management, L.P. (&quot;BD Management&quot;) (of which Mr. Becker is a limited partner), and BD Management is the general partner of, and investment manager for, each of BD Partners I, Becker Drapkin QP and Becker Drapkin, L.P. and provides investment advisory services for the Managed Account.  Mr. Becker disclaims beneficial ownership in such shares of 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>2010-10-13</signatureDate>
    </ownerSignature>
</ownershipDocument>
