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

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2007-10-15</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000883697</issuerCik>
        <issuerName>REGEN BIOLOGICS INC</issuerName>
        <issuerTradingSymbol>RGBI</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001313054</rptOwnerCik>
            <rptOwnerName>Rodkey William</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>411 HACKENSACK AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>HACKENSACK</rptOwnerCity>
            <rptOwnerState>NJ</rptOwnerState>
            <rptOwnerZipCode>07601</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Vice President</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>STOCK OPTION (RIGHT TO BUY)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>9.00</value>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2007-10-18</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>50000</value>
                    <footnoteId id="F2"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F3"/>
            </exerciseDate>
            <expirationDate>
                <value>2017-10-18</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Series E Convertible Preferred Stock</value>
                    <footnoteId id="F4"/>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>50000</value>
                    <footnoteId id="F2"/>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>50000</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>WARRANT</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>45.00</value>
                <footnoteId id="F5"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2007-10-15</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>13</value>
                    <footnoteId id="F6"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2007-10-15</value>
            </exerciseDate>
            <expirationDate>
                <value>2012-06-21</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>SERIES D CONVERTIBLE PREFERRED STOCK</value>
                    <footnoteId id="F7"/>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>13</value>
                    <footnoteId id="F6"/>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>13</value>
                    <footnoteId id="F6"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">EXERCISE PRICE IS $0.09 PER SHARE OF COMMON STOCK IF OPTION IS EXERCISED AFTER MANDATORY CONVERSION OF SERIES E STOCK.</footnote>
        <footnote id="F2">EQUAL TO 5,000,000 SHARES OF COMMON STOCK AFTER MANDATORY CONVERSION OF THE SERIES E STOCK</footnote>
        <footnote id="F3">THE OPTION VESTS RATABLY ON A DAILY BASIS OVER FOUR YEARS FROM THE DATE OF GRANT.</footnote>
        <footnote id="F4">EACH SHARE OF SERIES E STOCK IS MANDATORILY CONVERTIBLE INTO 100 SHARES OF REGEN'S COMMON STOCK AT SUCH TIME AS (i) THE COMPANY'S CERTIFICATE OF INCORPORATION IS AMENDED TO INCREASE THE NUMBER OF AUTHORIZED SHARES OF COMMON STOCK OR (ii) UPON THE EFFECTIVENESS OF A REVERSE STOCK SPLIT OF THE COMMON STOCK, SUCH THAT THERE ARE A SUFFICIENT NUMBER OF SHARES OF COMMON STOCK TO EFFECT THE CONVERSION.</footnote>
        <footnote id="F5">EXERCISE PRICE IS $0.45 PER SHARE OF COMMON STOCK IF WARRANT IS EXERCISED AFTER MANDATORY CONVERSION OF SERIES D STOCK.</footnote>
        <footnote id="F6">EQUAL TO 1,300 SHARES OF COMMON STOCK AFTER MANDATORY CONVERSION OF THE SERIES D STOCK</footnote>
        <footnote id="F7">EACH SHARE OF SERIES D STOCK IS MANDATORILY CONVERTIBLE INTO 100 SHARES OF REGEN'S COMMON STOCK AT SUCH TIME AS (i) THE COMPANY'S CERTIFICATE OF INCORPORATION IS AMENDED TO INCREASE THE NUMBER OF AUTHORIZED SHARES OF COMMON STOCK OR (ii) UPON THE EFFECTIVENESS OF A REVERSE STOCK SPLIT OF THE COMMON STOCK, SUCH THAT THERE ARE A SUFFICIENT NUMBER OF SHARES OF COMMON STOCK TO EFFECT THE CONVERSION.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/S/ BRION D. UMIDI ATTORNEY IN FACT</signatureName>
        <signatureDate>2007-10-26</signatureDate>
    </ownerSignature>
</ownershipDocument>
