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

    <schemaVersion>X0508</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2025-12-12</periodOfReport>

    <dateOfOriginalSubmission>2025-12-15</dateOfOriginalSubmission>

    <issuer>
        <issuerCik>0001035267</issuerCik>
        <issuerName>INTUITIVE SURGICAL INC</issuerName>
        <issuerTradingSymbol>ISRG</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0002010300</rptOwnerCik>
            <rptOwnerName>Brosius Mark</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1020 KIFER ROAD</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>SUNNYVALE</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94086</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isOfficer>true</isOfficer>
            <officerTitle>See Remarks</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>true</aff10b5One>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2025-12-12</value>
                <footnoteId id="F2"/>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>312</value>
                    <footnoteId id="F2"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>547.36</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>595</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">The transaction took place in accordance with a Trading Plan that complies with SEC Rule 10b5-1 and expires on February 14, 2027.</footnote>
        <footnote id="F2">The third transaction line in Table I of the Form 4 filed by the Reporting Person on 12/15/2025 incorrectly reported the transaction details.  The transaction line as reported herein has been restated to correct the errors in the original Form 4. Except as otherwise noted in this footnote, all other information disclosed in the Reporting Person's original Form 4 was accurately reported.</footnote>
    </footnotes>

    <remarks>SVP &amp; Chief Mfg and Supply Chain Officer</remarks>

    <ownerSignature>
        <signatureName>By: Thanh Nhan Phan For: Brosius, Mark</signatureName>
        <signatureDate>2025-12-17</signatureDate>
    </ownerSignature>
</ownershipDocument>
