<SEC-DOCUMENT>0000740260-18-000164.txt : 20181002
<SEC-HEADER>0000740260-18-000164.hdr.sgml : 20181002
<ACCEPTANCE-DATETIME>20181002164610
ACCESSION NUMBER:		0000740260-18-000164
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20181001
FILED AS OF DATE:		20181002
DATE AS OF CHANGE:		20181002

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Martino Roxanne M
		CENTRAL INDEX KEY:			0001676558

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-10989
		FILM NUMBER:		181101981

	MAIL ADDRESS:	
		STREET 1:		353 NORTH CLARK STREET
		STREET 2:		SUITE 3300
		CITY:			CHICAGO
		STATE:			IL
		ZIP:			60654

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			VENTAS INC
		CENTRAL INDEX KEY:			0000740260
		STANDARD INDUSTRIAL CLASSIFICATION:	REAL ESTATE INVESTMENT TRUSTS [6798]
		IRS NUMBER:				611055020
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		353 N. CLARK STREET
		STREET 2:		SUITE 3300
		CITY:			CHICAGO
		STATE:			IL
		ZIP:			60654
		BUSINESS PHONE:		3126603800

	MAIL ADDRESS:	
		STREET 1:		353 N. CLARK STREET
		STREET 2:		SUITE 3300
		CITY:			CHICAGO
		STATE:			IL
		ZIP:			60654
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_153851315346833.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2018-10-01</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000740260</issuerCik>
        <issuerName>VENTAS INC</issuerName>
        <issuerTradingSymbol>VTR</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001676558</rptOwnerCik>
            <rptOwnerName>Martino Roxanne M</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>353 NORTH CLARK STREET</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 3300</rptOwnerStreet2>
            <rptOwnerCity>CHICAGO</rptOwnerCity>
            <rptOwnerState>IL</rptOwnerState>
            <rptOwnerZipCode>60654</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>2018-10-01</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>578.918</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>53.98</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>12615.066</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Common stock in the form of units granted under the Ventas Nonemployee Directors' Deferred Stock Compensation Plan (the &quot;Plan&quot;) in lieu of director fees pursuant to the director's deferral election.  Such units are payable solely in common stock and subject to the terms and conditions of the director's deferral election and the Plan.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Roxanne M. Martino, By: T. Richard Riney, Attorney-In-Fact</signatureName>
        <signatureDate>2018-10-02</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
