<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0203</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2010-05-12</periodOfReport>

    <noSecuritiesOwned>0</noSecuritiesOwned>

    <issuer>
        <issuerCik>0000318154</issuerCik>
        <issuerName>AMGEN INC</issuerName>
        <issuerTradingSymbol>AMGN</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001491654</rptOwnerCik>
            <rptOwnerName>Dittrich Thomas J.W.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>ONE AMGEN CENTER DRIVE</rptOwnerStreet1>
            <rptOwnerStreet2>M/S 28-5-C</rptOwnerStreet2>
            <rptOwnerCity>THOUSAND OAKS</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>91320</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isOfficer>1</isOfficer>
            <officerTitle>VP, Finance &amp; CAO</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>12801</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeHolding>
            <securityTitle>
                <value>Nqso (Right to Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>69.83</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2007-05-15</value>
            </exerciseDate>
            <expirationDate>
                <value>2013-05-15</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>25000</value>
                    <footnoteId id="F2"/>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Nqso (Right to Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>62.55</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2008-04-26</value>
            </exerciseDate>
            <expirationDate>
                <value>2014-04-26</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>11000</value>
                    <footnoteId id="F3"/>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Nqso (Right to Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>42.13</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2009-04-29</value>
            </exerciseDate>
            <expirationDate>
                <value>2015-04-29</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>12000</value>
                    <footnoteId id="F4"/>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Nqso (Right to Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>50.44</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2010-04-28</value>
            </exerciseDate>
            <expirationDate>
                <value>2016-04-28</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>8000</value>
                    <footnoteId id="F5"/>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Nqso (Right to Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>58.43</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2011-04-26</value>
            </exerciseDate>
            <expirationDate>
                <value>2020-04-26</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>8600</value>
                    <footnoteId id="F6"/>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">These shares include 8,801 RSUs issued under the Company's equity plans which include:5,000 RSUs which vest in two equal annual installments of 2,500 each commencing 7/31/2010; 1,714 RSUs which vest in two equal annual installments of 857 each commencing 4/29/2011; 858 RSUs which vest in three equal annual installments of 286 each commencing 4/28/2011; and 1,229 RSUs which vest in three installments of 307 RSUs on 4/26/2011, 4/26/2012 and 4/26/2013 and one installment of 308 RSUs on 4/26/2014. Vested RSUs issued under the plans are paid in shares of the Company's Common Stock on a one-to-one basis.</footnote>
        <footnote id="F2">These options are fully exercisable.</footnote>
        <footnote id="F3">The option is exercisable in four equal annual installments. The first three installments are exercisable and the last installment of 2,750 options becomes exercisable on 4/26/2011.</footnote>
        <footnote id="F4">These options are exercisable in four equal annual installments. The first two installments are exercisable and the remaining two annual installments of 3,000 options each become exercisable commencing on 4/29/2011.</footnote>
        <footnote id="F5">These options are exercisable in four equal annual installments. The first installment is exercisable and the remaining three annual installments of 2,000 options each become exercisable commencing on 4/28/2011.</footnote>
        <footnote id="F6">These options are exercisable in four equal annual installments of 2,150 options each commencing 04/26/2011.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ Thomas J.W. Dittrich</signatureName>
        <signatureDate>2010-05-18</signatureDate>
    </ownerSignature>
</ownershipDocument>

