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

    <schemaVersion>X0206</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2018-11-13</periodOfReport>

    <noSecuritiesOwned>0</noSecuritiesOwned>

    <issuer>
        <issuerCik>0001253176</issuerCik>
        <issuerName>VAPOTHERM INC</issuerName>
        <issuerTradingSymbol>VAPO</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001439101</rptOwnerCik>
            <rptOwnerName>MORGENTHALER VENTURE PARTNERS IX LP</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>3200 ALPINE ROAD</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>PORTOLA VALLEY</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94028</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001666860</rptOwnerCik>
            <rptOwnerName>Morgenthaler Management Partners IX, LLC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>3200 ALPINE ROAD</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>PORTOLA VALLEY</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94028</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeHolding>
            <securityTitle>
                <value>Series A Convertible Preferred Stock</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F1"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>214285</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F6"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Series B Convertible Preferred Stock</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F2"/>
            </conversionOrExercisePrice>
            <exerciseDate>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F2"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>217803</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F6"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Series C Convertible Preferred Stock</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F3"/>
            </conversionOrExercisePrice>
            <exerciseDate>
                <footnoteId id="F3"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F3"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>359842</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F6"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Series D Convertible Preferred Stock</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F4"/>
            </conversionOrExercisePrice>
            <exerciseDate>
                <footnoteId id="F4"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F4"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>129418</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F6"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Series D-1 Convertible Preferred Stock</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F5"/>
            </conversionOrExercisePrice>
            <exerciseDate>
                <footnoteId id="F5"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F5"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>53951</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F6"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Each share of Series A Convertible Preferred Stock is convertible, for no additional consideration, into one (1) share of Common Stock at any time at the holder's election and automatically upon the consummation of a qualified public offering of the Issuer.  There is no expiration date for the Series A Convertible Preferred Stock.</footnote>
        <footnote id="F2">Each share of Series B Convertible Preferred Stock is convertible, for no additional consideration, into one (1) share of Common Stock at any time at the holder's election and automatically upon the consummation of a qualified public offering of the Issuer.  There is no expiration date for the Series B Convertible Preferred Stock.</footnote>
        <footnote id="F3">Each share of Series C Convertible Preferred Stock is convertible, for no additional consideration, into one (1) share of Common Stock at any time at the holder's election and automatically upon the consummation of a qualified public offering of the Issuer.  There is no expiration date for the Series C Convertible Preferred Stock.</footnote>
        <footnote id="F4">Each share of Series D Convertible Preferred Stock is convertible, for no additional consideration, into one (1) share of Common Stock at any time at the holder's election and automatically upon the consummation of a qualified public offering of the Issuer.  There is no expiration date for the Series D Convertible Preferred Stock.</footnote>
        <footnote id="F5">Each share of Series D-1 Convertible Preferred Stock is convertible, for no additional consideration, into one (1) share of Common Stock, provided that if the Issuer, subject to certain exceptions issues, or is deemed to have issued securities at a deemed price per share of the Issuer's Common Stock that is lower than $15.918 per share (the &quot;Lower Price&quot;), then each share of Series D-1 Convertible Preferred Stock will be convertible into such number of shares of the Issuer's Common Stock as is equal to the quotient obtained by dividing (1) $15.918 by (2) the Lower Price.</footnote>
        <footnote id="F6">The securities are held by Morgenthaler Venture Partners IX, L.P. (&quot;MVP IX&quot;). The general partner of MVP IX is Morgenthaler Management Partners IX, LLC (&quot;MMP IX&quot;). MMP IX may be deemed to indirectly beneficially own the securities directly held by MVP IX. MMP IX disclaims beneficial ownership of the securities held by MVP IX except to the extent of its pecuniary interest therein.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Morgenthaler Venture Partners IX, L.P., By: Morgenthaler Management Partners IX, LLC, its General Partner, By: /s/ Travis Boettner, Chief Financial Officer and Chief Compliance Officer</signatureName>
        <signatureDate>2018-11-13</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>Morgenthaler Management Partners IX, LLC, By: /s/ /s/ Travis Boettner, Chief Financial Officer and Chief Compliance Officer</signatureName>
        <signatureDate>2018-11-13</signatureDate>
    </ownerSignature>
</ownershipDocument>
