<?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>0001754423</rptOwnerCik>
            <rptOwnerName>McGrew Matthew</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>2200 PENNSYLVANIA AVENUE, NW</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 800W</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>EVP &amp; Chief Financial Officer</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>565.2</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>565.2</value>
                    <footnoteId id="F1"/>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2236.433</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">The reporting person will vest in all company contributions to the EDIP Stock Fund as follows: 100% upon the earlier of the reporting person's death, or upon retirement following at least 5 years of service  with Danaher and reaching the age of 55, or, if earlier, one-tenth per year of participation following five years of participation, in each case in accordance with the plan. Upon termination of employment, the vested portion of the EDIP Stock Fund is settled in Danaher common stock.</footnote>
    </footnotes>

    <remarks></remarks>

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