-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 LmUeHGez8XpyCz1Lf8ZGZcB2utzAjxb3/iQFCvn7Qb3r+eGnLkqLMlok9KI/KYNi
 AZod1OQPYp6DgASjBY46rQ==

<SEC-DOCUMENT>0001179110-10-016277.txt : 20101118
<SEC-HEADER>0001179110-10-016277.hdr.sgml : 20101118
<ACCEPTANCE-DATETIME>20101118153135
ACCESSION NUMBER:		0001179110-10-016277
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20101116
FILED AS OF DATE:		20101118
DATE AS OF CHANGE:		20101118

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			CHRIETZBERG CHARLES T
		CENTRAL INDEX KEY:			0001019453

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-27666
		FILM NUMBER:		101202638

	MAIL ADDRESS:	
		STREET 1:		601 MUNRAS AVENUE
		CITY:			MONTEREY
		STATE:			CA
		ZIP:			93940

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			NORTHERN CALIFORNIA BANCORP INC
		CENTRAL INDEX KEY:			0001006820
		STANDARD INDUSTRIAL CLASSIFICATION:	STATE COMMERCIAL BANKS [6022]
		IRS NUMBER:				000000000
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		601 MUNRAS AVE
		CITY:			MONTEREY
		STATE:			CA
		ZIP:			93940
		BUSINESS PHONE:		4086494600

	MAIL ADDRESS:	
		STREET 1:		601 MUNRAS AVE
		CITY:			MONTEREY
		STATE:			CA
		ZIP:			93940

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	MONTEREY COUNTY BANK
		DATE OF NAME CHANGE:	19960131
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>FORM 4 -
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2010-11-16</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001006820</issuerCik>
        <issuerName>NORTHERN CALIFORNIA BANCORP INC</issuerName>
        <issuerTradingSymbol>NRLB</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001019453</rptOwnerCik>
            <rptOwnerName>CHRIETZBERG CHARLES T</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>601 MUNRAS AVE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>MONTEREY</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>93940</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chairman, President &amp; CEO</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>COMMON STOCK</value>
            </securityTitle>
            <transactionDate>
                <value>2010-11-16</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>4000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>2.25</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>745052</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes></footnotes>

    <ownerSignature>
        <signatureName>/s/Charles T. Chrietzberg, Jr.</signatureName>
        <signatureDate>2010-11-18</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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