-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
 LgonM4xj75coyzrNRZx6aL2ZAeti8Sb2co1YA/rgyEnkpCUU1UCkFQjiwNeAmBZr
 tFRScBJrWSAOnPJTOJYMAw==

<SEC-DOCUMENT>0001079973-06-000254.txt : 20060426
<SEC-HEADER>0001079973-06-000254.hdr.sgml : 20060426
<ACCEPTANCE-DATETIME>20060426174731
ACCESSION NUMBER:		0001079973-06-000254
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20060421
FILED AS OF DATE:		20060426
DATE AS OF CHANGE:		20060426

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			BARNHILL GREGORY HURD
		CENTRAL INDEX KEY:			0001273979

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-21019
		FILM NUMBER:		06782390

	BUSINESS ADDRESS:	
		STREET 1:		1725 GILLESPIE WAY
		CITY:			EL CAJON
		STATE:			CA
		ZIP:			92020

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			PURE BIOSCIENCE
		CENTRAL INDEX KEY:			0001006028
		STANDARD INDUSTRIAL CLASSIFICATION:	MISCELLANEOUS CHEMICAL PRODUCTS [2890]
		IRS NUMBER:				330530289
		STATE OF INCORPORATION:			CA
		FISCAL YEAR END:			0731

	BUSINESS ADDRESS:	
		STREET 1:		1725 GILLESPIE WAY
		STREET 2:		STE H
		CITY:			EL CAJON
		STATE:			CA
		ZIP:			92020
		BUSINESS PHONE:		6195968600

	MAIL ADDRESS:	
		STREET 1:		1725 GILLESPIE WAY
		STREET 2:		SUITE H
		CITY:			EL CAJON
		STATE:			CA
		ZIP:			92020

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	PURE BIOSCIENCES
		DATE OF NAME CHANGE:	20031029

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	INNOVATIVE MEDICAL SERVICES
		DATE OF NAME CHANGE:	19960122
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2006-04-21</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001006028</issuerCik>
        <issuerName>PURE BIOSCIENCE</issuerName>
        <issuerTradingSymbol>PURE</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001273979</rptOwnerCik>
            <rptOwnerName>BARNHILL GREGORY HURD</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1725 GILLESPIE WAY</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>EL CAJON</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>92020</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>205000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Option</value>
                <footnoteId id="F1"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>1.65</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2006-04-21</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>250000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2006-10-23</value>
            </exerciseDate>
            <expirationDate>
                <value>2011-04-21</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>250000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>250000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">This stock option grant is exempt from Section 16(b) pursuant to Rule 16b-3d</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Gregory H. Barnhill</signatureName>
        <signatureDate>2006-04-21</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
-----END PRIVACY-ENHANCED MESSAGE-----