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

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2004-05-13</periodOfReport>

    <issuer>
        <issuerCik>0001094286</issuerCik>
        <issuerName>WATER PIK TECHNOLOGIES INC</issuerName>
        <issuerTradingSymbol>PIK</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001185532</rptOwnerCik>
            <rptOwnerName>HEIMBUCH BABETTE E</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>23 CORPORATE PLAZA</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 246</rptOwnerStreet2>
            <rptOwnerCity>NEWPORT BEACH</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>92660</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2004-05-13</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>3000</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>11343</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Restricted Common Stock issued pursuant to 1999 Non-Employee Director Stock Compensation Plan, as amended.  Restrictions to be removed on the third anniversary of the date of grant.</footnote>
        <footnote id="F2">There is no purchase or sale price corresponding to a grant of restricted stock under the 1999 Non-Employee Director Stock Compensation Plan, as amended.  The restricted stock is not valued until the restrictions are removed.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Babette E. Heimbuch, by Richard D. Tipton pursuant to Power of Attorney previously filed with the SEC</signatureName>
        <signatureDate>2004-06-16</signatureDate>
    </ownerSignature>
</ownershipDocument>

