<SEC-DOCUMENT>0000898173-19-000034.txt : 20190204
<SEC-HEADER>0000898173-19-000034.hdr.sgml : 20190204
<ACCEPTANCE-DATETIME>20190204164725
ACCESSION NUMBER:		0000898173-19-000034
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20190131
FILED AS OF DATE:		20190204
DATE AS OF CHANGE:		20190204

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			HENSLEE GREGORY L
		CENTRAL INDEX KEY:			0001095228

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-21318
		FILM NUMBER:		19564536

	MAIL ADDRESS:	
		STREET 1:		233 S PATTERSON
		CITY:			SPRINGFIELD
		STATE:			MO
		ZIP:			65802

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			O REILLY AUTOMOTIVE INC
		CENTRAL INDEX KEY:			0000898173
		STANDARD INDUSTRIAL CLASSIFICATION:	RETAIL-AUTO & HOME SUPPLY STORES [5531]
		IRS NUMBER:				274358837
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		233 S PATTERSON AVE
		CITY:			SPRINGFIELD
		STATE:			MO
		ZIP:			65802
		BUSINESS PHONE:		417-829-5878

	MAIL ADDRESS:	
		STREET 1:		233 S PATTERSON AVE
		CITY:			SPRINGFIELD
		STATE:			MO
		ZIP:			65802
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_154931683081321.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2019-01-31</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000898173</issuerCik>
        <issuerName>O REILLY AUTOMOTIVE INC</issuerName>
        <issuerTradingSymbol>ORLY</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001095228</rptOwnerCik>
            <rptOwnerName>HENSLEE GREGORY L</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>233 S. PATTERSON AVE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>SPRINGFIELD</rptOwnerCity>
            <rptOwnerState>MO</rptOwnerState>
            <rptOwnerZipCode>65802</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2019-01-31</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>943</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>344.66</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>16049</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2019-02-01</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>F</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>136</value>
                    <footnoteId id="F2"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>346.75</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>15913</value>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>21247</value>
                    <footnoteId id="F4"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Indirectly in Company's 401k plan and as trustee of a GRAT.</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Represents a restricted share award, which vests in three equal annual installments on January 31, 2020, 2021 and 2022.</footnote>
        <footnote id="F2">Represents shares withheld to satisfy payroll tax withholding obligations upon the vesting of restricted shares previously awarded.</footnote>
        <footnote id="F3">Total includes 1,073 shares held under the Company's Employee Stock Purchase Plan, 1,769 of unvested restricted share awards and 13,071 shares held directly by Mr. Henslee.</footnote>
        <footnote id="F4">Total includes 5,002 shares held in the Company's 401k plan and 16,245 shares held as trustee of a Grantor Retained Annuity Trust (GRAT).</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Greg Henslee</signatureName>
        <signatureDate>2019-02-04</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
