<SEC-DOCUMENT>0001209191-21-007886.txt : 20210204
<SEC-HEADER>0001209191-21-007886.hdr.sgml : 20210204
<ACCEPTANCE-DATETIME>20210204185600
ACCESSION NUMBER:		0001209191-21-007886
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20210202
FILED AS OF DATE:		20210204
DATE AS OF CHANGE:		20210204

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Ben-Natan Nimrod
		CENTRAL INDEX KEY:			0001399157

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-25826
		FILM NUMBER:		21592704

	MAIL ADDRESS:	
		STREET 1:		549 BALTIC WAY
		CITY:			SUNNYVALE
		STATE:			CA
		ZIP:			94089

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			HARMONIC INC
		CENTRAL INDEX KEY:			0000851310
		STANDARD INDUSTRIAL CLASSIFICATION:	RADIO & TV BROADCASTING & COMMUNICATIONS EQUIPMENT [3663]
		IRS NUMBER:				770201147
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		4300 NORTH FIRST STREET
		CITY:			SAN JOSE
		STATE:			CA
		ZIP:			95134
		BUSINESS PHONE:		4084906242

	MAIL ADDRESS:	
		STREET 1:		4300 NORTH FIRST STREET
		CITY:			SAN JOSE
		STATE:			CA
		ZIP:			95134

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	HARMONIC LIGHTWAVES INC
		DATE OF NAME CHANGE:	19950404
</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>2021-02-02</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001399157</rptOwnerCik>
            <rptOwnerName>Ben-Natan Nimrod</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>2590 ORCHARD PARKWAY</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>SAN JOSE</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>95131</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>SVP &amp; GM, Cable Access</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2021-02-02</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>36570</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>388466</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">These shares of common stock were acquired upon the vesting of performance-based restricted stock units (&quot;PRSUs&quot;) on February 2, 2021. The PRSUs were granted on February 24, 2020, and achievement of the performance condition for vesting was confirmed by the Compensation Committee of the Company's Board of Directors.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Laura Donovan
By Attorney-in-Fact: Laura Donovan</signatureName>
        <signatureDate>2021-02-04</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
