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

    <schemaVersion>X0203</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2010-06-28</periodOfReport>

    <noSecuritiesOwned>0</noSecuritiesOwned>

    <issuer>
        <issuerCik>0001318605</issuerCik>
        <issuerName>TESLA MOTORS INC</issuerName>
        <issuerTradingSymbol>TSLA</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001495013</rptOwnerCik>
            <rptOwnerName>Kohler Herbert</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>MERCEDESSTRASSE 137</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>STUTTGART</rptOwnerCity>
            <rptOwnerState>2M</rptOwnerState>
            <rptOwnerZipCode>70327</rptOwnerZipCode>
            <rptOwnerStateDescription>GERMANY</rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable></nonDerivativeTable>

    <derivativeTable>
        <derivativeHolding>
            <securityTitle>
                <value>Series E Preferred Stock</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F1"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>19901290</value>
                    <footnoteId id="F1"/>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See footnote.</value>
                    <footnoteId id="F2"/>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Series F Preferred Stock</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F1"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>2525933</value>
                    <footnoteId id="F1"/>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See footnote.</value>
                    <footnoteId id="F2"/>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Right to Buy (Common Stock)</value>
                <footnoteId id="F3"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>6.63</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2010-05-11</value>
            </exerciseDate>
            <expirationDate>
                <value>2016-12-03</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>33333</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See footnote.</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeHolding>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Each share of the Issuer's Series E preferred stock and Series F preferred stock will automatically convert into .333333 of a share of common stock upon the closing of the Issuer's initial public offering, and has no expiration date.</footnote>
        <footnote id="F2">The shares are owned directly by Blackstar Investco LLC, which is 60% owned by Daimler North America Corporation and 40% owned by Aabar Blackstar Holdings GmbH.  The reporting person is a vice president of Blackstar Investco LLC, and disclaims beneficial ownership of these shares, except to the extent of his pecuniary interest therein. This report shall not be deemed an admission that the reporting person is the beneficiary owner of such securities for Section 16 or any other purpose.</footnote>
        <footnote id="F3">1/4th of the shares subject to the option became vested and exercisable on May 11, 2010 and 1/48th of the shares subject to the option shall become vested and exercisable each month thereafter. The option is held by Daimler North America Corporation, and the reporting person disclaims beneficial ownership of the shares subject to the option, except to the extent of his pecuniary interest therein. This report shall not be deemed an admission that the reporting person is the beneficiary owner of such securities for Section 16 or any other purpose.</footnote>
    </footnotes>

    <remarks>The anticipated effective date of the Issuer's initial public offering is June 28, 2010.</remarks>

    <ownerSignature>
        <signatureName>/s/ Herbert Kohler</signatureName>
        <signatureDate>2010-06-25</signatureDate>
    </ownerSignature>
</ownershipDocument>
