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

    <schemaVersion>X0305</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2012-02-09</periodOfReport>

    <dateOfOriginalSubmission>2012-02-13</dateOfOriginalSubmission>

    <issuer>
        <issuerCik>0001021561</issuerCik>
        <issuerName>NU SKIN ENTERPRISES INC</issuerName>
        <issuerTradingSymbol>NUS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001184201</rptOwnerCik>
            <rptOwnerName>CHANG JOSEPH Y</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O NU SKIN ENTERPRISES, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>75 WEST CENTER STREET</rptOwnerStreet2>
            <rptOwnerCity>PROVO</rptOwnerCity>
            <rptOwnerState></rptOwnerState>
            <rptOwnerZipCode>84601</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chief Scientific Officer</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class A Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2012-02-09</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>2500</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>101200</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">On June 28, 2010, the reporting person was granted restricted stock units, which become eligible for vesting based on Nu Skin Enterprises, Inc.'s satisfaction of certain performance criteria. On February 9, 2012, the performance criteria were met, resulting in the shares becoming eligible for vesting.</footnote>
        <footnote id="F2">This amendment is being filed to include a transaction that was omitted from the original filing.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Clayton A. Jones as Attorney-in-Fact for Joseph Y. Chang</signatureName>
        <signatureDate>2012-04-20</signatureDate>
    </ownerSignature>
</ownershipDocument>
