<SUBMISSION>
<ACCESSION-NUMBER>0001209191-09-015720
<TYPE>4
<PUBLIC-DOCUMENT-COUNT>1
<PERIOD>20090310
<FILING-DATE>20090312
<DATE-OF-FILING-DATE-CHANGE>20090312
<ISSUER>
<COMPANY-DATA>
<CONFORMED-NAME>HARMONIC INC
<CIK>0000851310
<ASSIGNED-SIC>3663
<IRS-NUMBER>770201147
<STATE-OF-INCORPORATION>DE
<FISCAL-YEAR-END>1231
</COMPANY-DATA>
<BUSINESS-ADDRESS>
<STREET1>549 BALTIC WAY
<CITY>SUNNYVALE
<STATE>CA
<ZIP>94089
<PHONE>4085422500
</BUSINESS-ADDRESS>
<FORMER-COMPANY>
<FORMER-CONFORMED-NAME>HARMONIC LIGHTWAVES INC
<DATE-CHANGED>19950404
</FORMER-COMPANY>
</ISSUER>
<REPORTING-OWNER>
<OWNER-DATA>
<CONFORMED-NAME>KVAMME FLOYD E
<CIK>0001032451
<STATE-OF-INCORPORATION>CA
<FISCAL-YEAR-END>1231
</OWNER-DATA>
<FILING-VALUES>
<FORM-TYPE>4
<ACT>34
<FILE-NUMBER>000-25826
<FILM-NUMBER>09675240
</FILING-VALUES>
<BUSINESS-ADDRESS>
<PHONE>4084148868
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>C/O POWER INTEGRATIONS
<STREET2>5245 HELLYER AVE
<CITY>SAN JOSE
<STATE>CA
<ZIP>95138
</MAIL-ADDRESS>
</REPORTING-OWNER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc4.xml
<DESCRIPTION>FORM 4 SUBMISSION
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2009-03-10</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000851310</issuerCik>
        <issuerName>HARMONIC INC</issuerName>
        <issuerTradingSymbol>HLIT</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001032451</rptOwnerCik>
            <rptOwnerName>KVAMME FLOYD E</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>549 BALTIC WAY</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>SUNNYVALE</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94089</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
                <footnoteId id="F1"/>
            </securityTitle>
            <transactionDate>
                <value>2009-03-10</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>14209</value>
                    <footnoteId id="F2"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>493162</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Each restricted stock unit represents a contingent right to receive one share of HLIT common stock.</footnote>
        <footnote id="F2">The award is for 14,209 restricted stock units which vest in one annual installment on February 15, 2010. Vested shares will be delivered to the reporting person on or immediately following February 15, 2010.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Laura Donovan
By Attorney-in-Fact: Laura Donovan</signatureName>
        <signatureDate>2009-03-12</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SUBMISSION>
