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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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<SEC-DOCUMENT>0001012975-10-000425.txt : 20101213
<SEC-HEADER>0001012975-10-000425.hdr.sgml : 20101213
<ACCEPTANCE-DATETIME>20101213192133
ACCESSION NUMBER:		0001012975-10-000425
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20101209
FILED AS OF DATE:		20101213
DATE AS OF CHANGE:		20101213

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			APPLE TREE PARTNERS I LP
		CENTRAL INDEX KEY:			0001095799

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-34256
		FILM NUMBER:		101249143

	BUSINESS ADDRESS:	
		STREET 1:		ONE GORHAM ISLAND
		CITY:			WESTPORT
		STATE:			CT
		ZIP:			06880

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			HeartWare International, Inc.
		CENTRAL INDEX KEY:			0001389072
		STANDARD INDUSTRIAL CLASSIFICATION:	SURGICAL & MEDICAL INSTRUMENTS & APPARATUS [3841]
		IRS NUMBER:				980498958
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		14000 NW 57TH COURT
		CITY:			MIAMI LAKES
		STATE:			FL
		ZIP:			33014
		BUSINESS PHONE:		508-739-0841

	MAIL ADDRESS:	
		STREET 1:		205 NEWBURY STREET
		STREET 2:		SUITE 101
		CITY:			FRAMINGHAM
		STATE:			MA
		ZIP:			01701

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	HeartWare LTD
		DATE OF NAME CHANGE:	20070206
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2010-12-09</periodOfReport>

    <issuer>
        <issuerCik>0001389072</issuerCik>
        <issuerName>HeartWare International, Inc.</issuerName>
        <issuerTradingSymbol>HTWR</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001095799</rptOwnerCik>
            <rptOwnerName>APPLE TREE PARTNERS I LP</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>ONE BROADWAY, 14TH FLOOR</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>CAMBRIDGE</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02142</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-12-09</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>1000000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>77.855</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1673962</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Pursuant to an underwriting agreement (the &quot;Underwriting Agreement&quot;), dated as of December 9, 2010, among Apple Tree Partners I, L.P. (the &quot;Selling Stockholder&quot;), the Issuer, and the underwriters named therein (the &quot;Underwriters&quot;), the Selling Stockholder has agreed to sell an aggregate of 1,000,000 shares of common stock, par value $0.001 per share (&quot;Common Stock&quot;), of the Issuer to the Underwriters, in connection with a registered public offering.  The closing of the sale of such shares is expected to occur on or about December 15, 2010, and is subject to customary conditions.</footnote>
        <footnote id="F2">The securities held by the reporting person prior to the sale reported herein were previously reported as ordinary shares in HeartWare LTD. (ASX: HTW) prior to the Issuer's redomiciliation from Australia to Delaware.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Seth L. Harrison, Managing Member of Apple Tree Ventures I, LLC, general partner of Apple Tree Partners I, L.P.</signatureName>
        <signatureDate>2010-12-13</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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