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

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2014-02-05</periodOfReport>

    <notSubjectToSection16>1</notSubjectToSection16>

    <issuer>
        <issuerCik>0001346830</issuerCik>
        <issuerName>Cara Therapeutics, Inc.</issuerName>
        <issuerTradingSymbol>CARA</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001257444</rptOwnerCik>
            <rptOwnerName>ALTA BIOPHARMA PARTNERS III LP</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>ONE EMBARCADERO CENTER, 37TH FLOOR</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>SAN FRANCISCO</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94111</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001280234</rptOwnerCik>
            <rptOwnerName>ALTA BIOPHARMA MANAGEMENT III LLC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O ALTA PARTNERS</rptOwnerStreet1>
            <rptOwnerStreet2>ONE EMBARCADERO CENTER, 37TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>SAN FRANCISCO</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94111</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001280265</rptOwnerCik>
            <rptOwnerName>ALTA BIOPHARMA PARTNERS III GMBH &amp; CO BETEILIGUNGS KG</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O ALTA PARTNERS</rptOwnerStreet1>
            <rptOwnerStreet2>ONE EMBARCADERO CENTER, 37TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>SAN FRANCISCO</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94111</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001280238</rptOwnerCik>
            <rptOwnerName>ALTA EMBARCADERO BIOPHARMA PARTNERS III LLC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O ALTA PARTNERS</rptOwnerStreet1>
            <rptOwnerStreet2>ONE EMBARCADERO CENTER, 37TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>SAN FRANCISCO</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94111</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001198321</rptOwnerCik>
            <rptOwnerName>CHAMPSI FARAH</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O ALTA PARTNERS</rptOwnerStreet1>
            <rptOwnerStreet2>ONE EMBARCADERO CENTER, 37TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>SAN FRANCISCO</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94111</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001211840</rptOwnerCik>
            <rptOwnerName>HURWITZ EDWARD</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O ALTA PARTNERS</rptOwnerStreet1>
            <rptOwnerStreet2>ONE EMBARCADERO CENTER, 37TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>SAN FRANCISCO</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94111</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001198332</rptOwnerCik>
            <rptOwnerName>PENHOET EDWARD</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O ALTA PARTNERS</rptOwnerStreet1>
            <rptOwnerStreet2>ONE EMBARCADERO CENTER, 37TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>SAN FRANCISCO</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94111</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2014-02-05</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
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                <footnoteId id="F1"/>
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            <transactionTimeliness>
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                <transactionPricePerShare>
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                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Footnote</value>
                    <footnoteId id="F2"/>
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        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
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                <natureOfOwnership>
                    <value>See Footnote</value>
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                <natureOfOwnership>
                    <value>See Footnote</value>
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                    <value>See Footnote</value>
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                <natureOfOwnership>
                    <value>See Footnote</value>
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                    <value>See Footnote</value>
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                    <value>See Footnote</value>
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            <expirationDate>
                <footnoteId id="F3"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>531442</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Footnote</value>
                    <footnoteId id="F2"/>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Series D Preferred Stock</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F3"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2014-02-05</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>C</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>89227</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F3"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F3"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>35691</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Footnote</value>
                    <footnoteId id="F4"/>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Series D Preferred Stock</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F3"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2014-02-05</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>C</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>32742</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F3"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F3"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>13097</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Footnote</value>
                    <footnoteId id="F5"/>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The Series C Preferred Stock held by the reporting persons automatically converted on a 1-for-2.1129 basis into shares of common stock upon the closing of the issuer's initial public offering.</footnote>
        <footnote id="F2">These shares are held of record by Alta BioPharma Partners III, L.P. (&quot;ABP III&quot;). Alta BioPharma Management III, LLC (&quot;ABM III&quot;) is the general partner of ABP III. Edward Hurwitz, a director of the issuer, Farah Champsi and Edward Penhoet are directors of ABM III and may be deemed to share dispositive and voting power over the shares held by ABP III. Each of the reporting persons disclaims beneficial ownership of these securities except to the extent of his, her or its respective pecuniary interest therein.</footnote>
        <footnote id="F3">The Series D Preferred Stock held by the reporting persons automatically converted on a 1-for-2.5 basis into shares of common stock upon the closing of the issuer's initial public offering.</footnote>
        <footnote id="F4">These shares are held of record by Alta BioPharma Partners III GmbH &amp; Co. Beteiligungs KG (&quot;GmbH&quot;). ABM III is the managing limited partner of GmbH. Edward Hurwitz, a director of the issuer, Farah Champsi and Edward Penhoet are directors of ABM III and may be deemed to share dispositive and voting power over the shares held by GmbH. Each of the reporting persons disclaims beneficial ownership of these securities except to the extent of his, her or its respective pecuniary interest therein.</footnote>
        <footnote id="F5">These shares are held of record by Alta Embarcadero BioPharma Partners III, LLC (&quot;Embarcadero&quot;). Edward Hurwitz, a director of the issuer, Farah Champsi and Edward Penhoet are the managers of Embarcadero and may be deemed to share dispositive and voting power over the shares held by Embarcadero. Each of the reporting persons disclaims beneficial ownership of these securities except to the extent of his, her or its respective pecuniary interest therein.</footnote>
    </footnotes>

    <remarks>Please note that all of these reporting persons are no longer subject to Section 16 Form 4 or Form 5 obligations, with the exception of Edward Hurwitz, who will have an ongoing Section 16 reporting obligation as a director of the issuer.</remarks>

    <ownerSignature>
        <signatureName>/s/Darren DeStefano, Attorney-in-Fact</signatureName>
        <signatureDate>2014-02-05</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>Darren DeStefano, Attorney-in-Fact</signatureName>
        <signatureDate>2014-02-05</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>Darren DeStefano, Attorney-in-Fact</signatureName>
        <signatureDate>2014-02-05</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>Darren DeStefano, Attorney-in-Fact</signatureName>
        <signatureDate>2014-02-05</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>Darren DeStefano, Attorney-in-Fact</signatureName>
        <signatureDate>2014-02-05</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>Darren DeStefano, Attorney-in-Fact</signatureName>
        <signatureDate>2014-02-05</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>Darren DeStefano, Attorney-in-Fact</signatureName>
        <signatureDate>2014-02-05</signatureDate>
    </ownerSignature>
</ownershipDocument>
