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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 U4yFkrVWZIFJOgQZ6kESviwZ1zE3ORRRaT6nV2r4dACozCfOVZxldqwTS++96Ynp
 2GkxMFIEnGSDgRm6jQaSUw==

<SEC-DOCUMENT>0000904454-04-000636.txt : 20041022
<SEC-HEADER>0000904454-04-000636.hdr.sgml : 20041022
<ACCEPTANCE-DATETIME>20041022152705
ACCESSION NUMBER:		0000904454-04-000636
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20041020
FILED AS OF DATE:		20041022
DATE AS OF CHANGE:		20041022

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			NUVASIVE INC
		CENTRAL INDEX KEY:			0001142596
		STANDARD INDUSTRIAL CLASSIFICATION:	SURGICAL & MEDICAL INSTRUMENTS & APPARATUS [3841]
		IRS NUMBER:				330768598
		STATE OF INCORPORATION:			DE

	BUSINESS ADDRESS:	
		STREET 1:		10065 OLD GROVE RD
		CITY:			SAN DIEGO
		STATE:			CA
		ZIP:			92131
		BUSINESS PHONE:		8582717070

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			BLAIR JAMES C
		CENTRAL INDEX KEY:			0001024000
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		STATE OF INCORPORATION:			CA
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-50744
		FILM NUMBER:		041091824

	BUSINESS ADDRESS:	
		STREET 1:		5880 PACIFIC CENTER BLVD
		CITY:			SAN DIEGO
		STATE:			CA
		ZIP:			92121-4204
		BUSINESS PHONE:		6194572553

	MAIL ADDRESS:	
		STREET 1:		5880 PACIFIC CENTER BLVD
		CITY:			SAN DIEGO
		STATE:			CA
		ZIP:			92121-4204
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2004-10-20</periodOfReport>

    <issuer>
        <issuerCik>0001142596</issuerCik>
        <issuerName>NUVASIVE INC</issuerName>
        <issuerTradingSymbol>NUVA</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001024000</rptOwnerCik>
            <rptOwnerName>BLAIR JAMES C</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O DOMAIN ASSOCIATES, LLC</rptOwnerStreet1>
            <rptOwnerStreet2>ONE PALMER SQUARE</rptOwnerStreet2>
            <rptOwnerCity>PRINCETON</rptOwnerCity>
            <rptOwnerState>NJ</rptOwnerState>
            <rptOwnerZipCode>08542</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Stock Option (Right to Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>9.50</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2004-10-20</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>6000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2005-10-20</value>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <value>2014-10-20</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>6000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>6000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F2"/>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The option vests ratably on a monthly basis over one year (fully vested as of 10/20/05).</footnote>
        <footnote id="F2">The Reporting Person also indirectly beneficially owns i) 8,000 shares of Common Stock held by Domain Associates, L.L.C.; ii) 1,752,455 shares of Common Stock held by Domain Partners IV, L.P.; and iii) 31,204 shares of Common Stock held by DP IV Associates, L.P.  The Reporting Person is a managing member of Domain Associates, L.L.C. and a managing member of One Palmer Square Associates IV, L.L.C., the sole general partner of Domain Partners IV, L.P. and DP IV Associates, L.P.  Pursuant to Instruction 4(b)(iv) of Form 4, the Reporting Person has elected to report as indirectly beneficially owned the entire number of securities beneficially owned by each such entity.  The Reporting Person disclaims beneficial ownership of any securities, and any proceeds thereof, that exceed his or her pecuniary interest therein and/or that are not actually distributed to him or her.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Kathleen K. Schoemaker, Attorney-in-Fact</signatureName>
        <signatureDate>2004-10-22</signatureDate>
    </ownerSignature>
</ownershipDocument>

</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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