-----BEGIN PRIVACY-ENHANCED MESSAGE-----
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>0001355566-07-000002.txt : 20070524
<SEC-HEADER>0001355566-07-000002.hdr.sgml : 20070524
<ACCEPTANCE-DATETIME>20070524172036
ACCESSION NUMBER:		0001355566-07-000002
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20070524
FILED AS OF DATE:		20070524
DATE AS OF CHANGE:		20070524

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Cobbs Jerald S
		CENTRAL INDEX KEY:			0001355566

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-15360
		FILM NUMBER:		07877780

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		503-692-8001

	MAIL ADDRESS:	
		STREET 1:		20245 SW 95TH AVENUE
		CITY:			TUALATIN
		STATE:			OR
		ZIP:			97062

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			BIOJECT MEDICAL TECHNOLOGIES INC
		CENTRAL INDEX KEY:			0000810084
		STANDARD INDUSTRIAL CLASSIFICATION:	SURGICAL & MEDICAL INSTRUMENTS & APPARATUS [3841]
		IRS NUMBER:				931099680
		STATE OF INCORPORATION:			OR
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		20245 SW 95TH AVENUE
		CITY:			TUALATIN
		STATE:			OR
		ZIP:			97062
		BUSINESS PHONE:		5036928001

	MAIL ADDRESS:	
		STREET 1:		20245 SW 95TH AVENUE
		CITY:			TUALATIN
		STATE:			OR
		ZIP:			97062

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	BIOJECT MEDICAL SYSTEMS LTD
		DATE OF NAME CHANGE:	19920703
</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>2007-05-24</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000810084</issuerCik>
        <issuerName>BIOJECT MEDICAL TECHNOLOGIES INC</issuerName>
        <issuerTradingSymbol>BJCT</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001355566</rptOwnerCik>
            <rptOwnerName>Cobbs Jerald S</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>20245 SW 95TH AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>TUALATIN</rptOwnerCity>
            <rptOwnerState>OR</rptOwnerState>
            <rptOwnerZipCode>97062</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>BJCT Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2007-05-24</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>3500</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>7000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Restricted Stock Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F2"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2007-05-24</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>3500</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2007-05-24</value>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F1"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>BJCT Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>3500</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">No expiration date</footnote>
        <footnote id="F2">Each restricted stock unit represents a contingent right to receive one share of BJCT common stock.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Christine M. Farrell, Attorney-in-fact</signatureName>
        <signatureDate>2007-05-24</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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