UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                            SCHEDULE 14A INFORMATION

           Proxy Statement Pursuant to Section 14(a) of the Securities
                      Exchange Act of 1934

Filed by the Registrant [X]

Filed by a Party other than the Registrant [_]

Check the appropriate box:

[_] Preliminary Proxy Statement

[_] Confidential, for Use of the Commission Only (as permitted by Rule
    14a-6(e)(2))

[ ] Definitive Proxy Statement

[ ] Definitive Additional Materials

[X] Soliciting Material under Section 240.14a-12

                               Unocal Corporation
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                (Name of Registrant as Specified In Its Charter)


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    (Name of Person(s) Filing Proxy Statement, if other than the Registrant)

Payment of Filing Fee (Check the appropriate box):

[X] No fee required

[_] Fee computed on table below per Exchange Act Rules 14a-6(1)(4) and 0-11.

    (1) Title of each class of securities to which transaction applies:

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    (2) Aggregate number of securities to which transaction applies:

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    (3) Per unit price or other underlying value of transaction computed
        pursuant to Exchange Act Rule 0-11 (Set forth the amount on which the
        filing fee is calculated and state how it was determined):

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    (4) Proposed maximum aggregate value of transaction:

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    (5) Total fee paid:

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 [_] Fee paid previously with preliminary materials.

 [_] Check box if any part of the fee is offset as provided by Exchange Act Rule
     0-11(a)(2)and identify the filing for which the offsetting fee was paid
     previously. Identify the previous filing by registration statement number,
     or the Form or Schedule and the date of its filing.

     (1) Amount Previously Paid:

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     (2) Form, Schedule or Registration Statement No.:

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     (3) Filing Party:

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     (4) Date Filed:

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April 12, 2004

To:   Employees with Unocal Stock in the Unocal Savings Plan and
      Employees with Restricted Stock

From: Bryan J. Pechersky, Corporate Secretary

Re:   Delivery of 2003 Annual Report and 2004 Proxy Statement
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Unocal's 2003 Annual Report and 2004 Proxy Statement are now available online
for employees. Both documents are accessible in the Outlook Public Folders and
on the Unocal homepage.

The complete documents are posted in pdf format. If not already installed, you
will need to have Adobe Acrobat Reader installed on your computer to view these
documents. Instructions for downloading and installing Acrobat Reader are
available from both locations. If you have any questions, please contact the
IT Help Desk at (877) 888-7676.

OUTLOOK FOLDER:
[Graphic: Outlook folder link appears hers]

UNOCAL HOMEPAGE: HTTP://WWW.UNOCAL.COM Click on "2003 Annual Report"
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and "2004 Proxy Statement."

A proxy card to vote your Savings Plan shares and any shares of restricted stock
you own for this year's annual meeting is scheduled to arrive at your address
within the next three weeks through the U.S. Mail. If you have requested hard
copies of the annual report or proxy statement (by e-mail or fax to David
Whitehurst), those will be mailed to you as well.

Your vote is important. When your proxy card comes in the mail, you may choose
to vote by internet, phone, or mail. The website and phone number for Mellon
Investor Services, the independent proxy tabulator and Unocal's Transfer Agent,
and a control number, are on the proxy card to vote by internet or phone. A
return envelope is provided if you decide to return your vote by mail. The proxy
tabulator will keep your vote confidential regardless of which voting method you
choose.

Thank you for your attention to this important matter.

IMPORTANT INFORMATION ABOUT PROXY STATEMENT:

Unocal Corporation filed the 2004 Proxy Statement with the Securities and
Exchange Commission on April 12, 2004. You are urged to read the proxy statement
because it contains important information. In addition to the free on-line
access to the proxy statement described above, you may obtain, free of charge, a
copy of the proxy statement as filed with the Securities and Exchange Commission
at the Securities and Exchange Commission's website, WWW.SEC.GOV, and Unocal
Corporation will also provide you a copy of the proxy statement free of charge
upon request.

Unocal Corporation and its directors and executive officers and certain other of
its employees may be soliciting proxies from stockholders of Unocal Corporation
with respect to the proposals described in the proxy statement. Information
concerning the participants in the proxy solicitation and any direct or indirect
interests of those participants in the solicitation are set forth in the proxy
statement.