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

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2019-02-01</periodOfReport>

    <issuer>
        <issuerCik>0000313616</issuerCik>
        <issuerName>DANAHER CORP /DE/</issuerName>
        <issuerTradingSymbol>DHR</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001608367</rptOwnerCik>
            <rptOwnerName>King William</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>2200 PENNSYLVANIA AVENUE, NW, SUITE 800W</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>WASHINGTON</rptOwnerCity>
            <rptOwnerState>DC</rptOwnerState>
            <rptOwnerZipCode>20037</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>SVP, Strategic Development</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Executive Deferred Incentive Program -- Danaher Stock Fund</value>
                <footnoteId id="F1"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>0</value>
                <footnoteId id="F2"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2019-02-01</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>1181.2</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>109.30</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F3"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F3"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>1181.2</value>
                    <footnoteId id="F1"/>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>16598.548</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Represents the Company's annual contribution to the Danaher stock fund (the &quot;EDIP Stock Fund&quot;) in the reporting person's Executive Deferred Incentive Program (the &quot;EDIP&quot;) account.  The Company contributions are deemed to be invested in a number of unfunded, notional shares of Danaher common stock, calculated by dividing the contribution amount by the closing price of Danaher common stock as reported on the NYSE on the last trading day of the year immediately preceding the year in which the contribution is made. The price shown in Table II, Column 8 is the closing price per share of Danaher common stock as reported on the NYSE on the date the contribution was actually made (or the closing price for the immediately preceding business day, if such date is not a business day).</footnote>
        <footnote id="F2">The notional shares convert on a one-for-one basis.</footnote>
        <footnote id="F3">All contributions to the reporting person's EDIP Stock Fund are immediately vested. Upon termination of employment, the EDIP Stock Fund is settled in shares of Danaher common stock.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>James F. O'Reilly, attorney-in-fact for William King</signatureName>
        <signatureDate>2019-02-04</signatureDate>
    </ownerSignature>
</ownershipDocument>
