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

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2005-07-20</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000726514</issuerCik>
        <issuerName>ELECTRO SCIENTIFIC INDUSTRIES INC</issuerName>
        <issuerTradingSymbol>ESIO</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001270988</rptOwnerCik>
            <rptOwnerName>MUSTOE KERRY L</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>13900 NW SCIENCE PARK DR.</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>PORTLAND</rptOwnerCity>
            <rptOwnerState>OR</rptOwnerState>
            <rptOwnerZipCode>97229</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Controller &amp; CAO</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>469</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Non-Qualified Stock Option (right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>19.84</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2005-07-20</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>15000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2006-05-26</value>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <value>2015-07-20</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>15000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>15000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeHolding>
            <securityTitle>
                <value>Incentive Stock Option (right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>20.16</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2004-09-02</value>
                <footnoteId id="F3"/>
            </exerciseDate>
            <expirationDate>
                <value>2013-09-01</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>15000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>15000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Incentive Stock Option (right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>25</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2004-11-13</value>
                <footnoteId id="F4"/>
            </exerciseDate>
            <expirationDate>
                <value>2013-11-12</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>976</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>976</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Non-Qualified Stock Option (right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>16.92</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2006-04-20</value>
                <footnoteId id="F5"/>
            </exerciseDate>
            <expirationDate>
                <value>2015-04-19</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>9000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>9000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
        <derivativeHolding>
            <securityTitle>
                <value>Non-Qualified Stock Option (right to buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>25</value>
            </conversionOrExercisePrice>
            <exerciseDate>
                <value>2004-11-13</value>
                <footnoteId id="F4"/>
            </exerciseDate>
            <expirationDate>
                <value>2013-11-12</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>7024</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>7024</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeHolding>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Option becomes 100% exercisable on 5/26/06.  The shares underlying the option are restricted from being sold for a period of 3 years from the grant date.</footnote>
        <footnote id="F2">No purchase price is paid upon grant of option.</footnote>
        <footnote id="F3">Options become exercisable for 25% of the shares on the first four anniversaries of the grant date.</footnote>
        <footnote id="F4">Options become exercisable for 25% of the shares on the first four anniversaries of the grant date.  Effective June 28, 2004 the vesting of the option was accelerated to be 100% vested on June 28, 2004.  As a result of this vesting acceleration, the original ISO / NQ split of the total shares granted was adjusted if necessary to comply with the IRS limitation.</footnote>
        <footnote id="F5">Option becomes 100% exercisable on the first anniversary of grant date.  The shares underlying the option are restricted from being sold for a period of 3 years from the grant date.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Kerry L. Mustoe</signatureName>
        <signatureDate>2005-07-22</signatureDate>
    </ownerSignature>
</ownershipDocument>
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X0202
4
2005-07-20
0
0000726514
ELECTRO SCIENTIFIC INDUSTRIES INC
ESIO
0001270988
MUSTOE KERRY L
13900 NW SCIENCE PARK DR.
PORTLAND
OR
97229
0
1
0
0
Controller & CAO
Common Stock
469
D
Non-Qualified Stock Option (right to buy)
19.84
2005-07-20
4
A
0
15000
A
2006-05-26
2015-07-20
Common Stock
15000
15000
D
Incentive Stock Option (right to buy)
20.16
2004-09-02
2013-09-01
Common Stock
15000
15000
D
Incentive Stock Option (right to buy)
25
2004-11-13
2013-11-12
Common Stock
976
976
D
Non-Qualified Stock Option (right to buy)
16.92
2006-04-20
2015-04-19
Common Stock
9000
9000
D
Non-Qualified Stock Option (right to buy)
25
2004-11-13
2013-11-12
Common Stock
7024
7024
D
Option becomes 100% exercisable on 5/26/06.  The shares underlying the option are restricted from being sold for a period of 3 years from the grant date.
No purchase price is paid upon grant of option.
Options become exercisable for 25% of the shares on the first four anniversaries of the grant date.
Options become exercisable for 25% of the shares on the first four anniversaries of the grant date.  Effective June 28, 2004 the vesting of the option was accelerated to be 100% vested on June 28, 2004.  As a result of this vesting acceleration, the original ISO / NQ split of the total shares granted was adjusted if necessary to comply with the IRS limitation.
Option becomes 100% exercisable on the first anniversary of grant date.  The shares underlying the option are restricted from being sold for a period of 3 years from the grant date.
Kerry L. Mustoe
2005-07-22