<?xml version="1.0" encoding="utf-8"?>
<ownershipDocument>
    <schemaVersion>X0201</schemaVersion>

    <documentType>4</documentType>
  <periodOfReport>2003-10-31</periodOfReport>
  <notSubjectToSection16>0</notSubjectToSection16>
    <issuer>
        <issuerCik>0001005286</issuerCik>
        <issuerName>LANDEC CORP \CA\</issuerName>
        <issuerTradingSymbol>LNDC</issuerTradingSymbol>
  </issuer>
  <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001068799</rptOwnerCik>
            <rptOwnerName>JONES KENNETH E</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O GLOBE WIRELESS</rptOwnerStreet1>
            <rptOwnerStreet2>550 PILGRIM DRIVE, STE. F</rptOwnerStreet2>
            <rptOwnerCity>FOSTER CITY</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94404</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
            <reportingOwnerRelationship>
      <isDirector>1</isDirector>
      <isOfficer>0</isOfficer>
      <isTenPercentOwner>0</isTenPercentOwner>
      <isOther>0</isOther>
    </reportingOwnerRelationship>
  </reportingOwner>
  <derivativeTable>
    <derivativeTransaction>
      <securityTitle>
        <value>Series B Preferred Stock</value>
      </securityTitle>
      <conversionOrExercisePrice>
        <value>35.00</value>
      </conversionOrExercisePrice>
      <transactionDate>
        <value>2003-10-31</value>
      </transactionDate>
      <transactionCoding>
        <transactionFormType>4</transactionFormType>
        <transactionCode>J</transactionCode>
        <equitySwapInvolved>0</equitySwapInvolved>
        <footnoteId id="F1"/>
      </transactionCoding>
      <transactionTimeliness>
        <value></value>
      </transactionTimeliness>
      <transactionAmounts>
        <transactionShares>
          <value>3282</value>
        </transactionShares>
        <transactionPricePerShare>
          <value>35.00</value>
        </transactionPricePerShare>
        <transactionAcquiredDisposedCode>
          <value>A</value>
        </transactionAcquiredDisposedCode>
      </transactionAmounts>
      <exerciseDate>
        <footnoteId id="F4"/>
      </exerciseDate>
      <expirationDate>
        <footnoteId id="F5"/>
      </expirationDate>
      <underlyingSecurity>
        <underlyingSecurityTitle>
          <value>Common Stock</value>
        </underlyingSecurityTitle>
        <underlyingSecurityShares>
          <value>32820</value>
          <footnoteId id="F2"/>
        </underlyingSecurityShares>
      </underlyingSecurity>
      <postTransactionAmounts>
        <sharesOwnedFollowingTransaction>
          <value>167381</value>
        </sharesOwnedFollowingTransaction>
      </postTransactionAmounts>
      <ownershipNature>
        <directOrIndirectOwnership>
          <value>I</value>
        </directOrIndirectOwnership>
        <natureOfOwnership>
          <value>By Trust Seahawk Ranch Irrevocable Trust</value>
          <footnoteId id="F3"/>
        </natureOfOwnership>
      </ownershipNature>
    </derivativeTransaction>
  </derivativeTable>
  <footnotes>
    <footnote id="F1">The 3,282 shares of Series B Preferred Stock represent a stock dividend issued to Seahawk Ranch Irrevocable Trust (the "Seahawk Trust").  The Seahawk Trust is the sole shareholder of shares of Series B Preferred Stock.</footnote>
    <footnote id="F2">Shares of Series B Prefererd Stock convert on a 10 to 1 basis into Common Stock.</footnote>
    <footnote id="F3">Mr. Jones is a Trustee of the Seahawk Trust.</footnote>
    <footnote id="F4">All shares are currently exercisable.</footnote>
    <footnote id="F5">Not applicable.</footnote>
  </footnotes>
  <ownerSignature>
    <signatureName>Gregory Scott Skinner by power of attorney</signatureName>
    <signatureDate>2003-10-31</signatureDate>
  </ownerSignature>
</ownershipDocument>

