AS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION ON AUGUST 6, 2004
                                                  Registration No: 333-_________

                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549


                                    FORM S-8
             REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933

                                   Nexen INC.
             (Exact name of registrant as specified in its charter)

                  CANADA                                 98-6000202
     (State or other jurisdiction of           (IRS Employer Identification No.)
      incorporation or organization)
                    _________________________________________

                              801 - 7th Avenue S.W.
                        Calgary, Alberta, Canada T2P 3P7
                              Phone: (403) 699-4000
          (Address, including zip code, and telephone number, including
             area code, of registrant's principal executive offices)


                               NEXEN SAVINGS PLAN
                            (Full title of the plan)

                           Nexen Petroleum U.S.A. Inc.
                                12790 Merit Drive
                                    Suite 800
                               Dallas, Texas 75251
                     (Name and address of agent for service)


                                 (972) 450-4600
          (Telephone number, including area code, of agent for service)
                              ____________________

<TABLE>
<CAPTION>
                                   COPIES TO:
<S>                                       <C>                                  <C>
          John B. McWilliams                        Gregg Radetsky                    Edwin S. Maynard
Senior Vice President, General Counsel    Vice President and General Counsel           Andrew J. Foley
            and Secretary                     Nexen Petroleum U.S.A. Inc.      Paul, Weiss, Rifkind, Wharton &
              Nexen Inc.                           12790 Merit Drive                    Garrison LLP
        801 - 7th Avenue S.W.                          Suite 800                 1285 Avenue of the Americas
   Calgary, Alberta, Canada T2P 3P7               Dallas, Texas 75251           New York, New York 10019-6064
</TABLE>

<TABLE>
                         CALCULATION OF REGISTRATION FEE
================================================================================================================
                                                     Proposed Maximum     Proposed Maximum
          Title of                Amount to be        Offering Price     Aggregate Offering       Amount of
 Securities to be Registered     Registered (1)(2)      Per Share (3)            Price         Registration Fee
----------------------------------------------------------------------------------------------------------------
<S>                               <C>                   <C>                <C>                    <C>
Common Shares, no par value       400,000 shares        $38.06             $15,224,000            $1,929
----------------------------------------------------------------------------------------------------------------
</TABLE>
(1)      This Registration Statement also applies to rights under the
         Registrant's Shareholder Rights Plan Agreement, which are attached to
         and tradable only with the common shares registered hereby. No
         registration fees are required for such rights as they will be issued
         for no additional consideration.
(2)      This Registration Statement shall, in accordance with Rule 416 under
         the Securities Act of 1933, as amended, be deemed to cover such
         additional shares as may be issued to prevent dilution resulting from
         stock splits, stock dividends or similar transactions.
(3)      Calculated in accordance with Rule 457(c) and (h)(1) under the
         Securities Act, as amended, and equal to the average of the high and
         low prices reported on the New York Stock Exchange on August 4, 2004, a
         date within five business days of the filing of this Registration
         Statement.

<PAGE>

                                EXPLANATORY NOTE

         We are filing this registration statement for the purpose of
registering, in accordance with General Instruction E of Form S-8, an additional
400,000 Common Shares, no par value, to be issued under the Registrant's Nexen
Savings Plan, formerly known as the CXY Savings Plan. We incorporate by
reference into this registration statement on Form S-8 our previously filed
registration statement on Form S-8, as amended (File No. 033-79666, filed on
June 2, 1994 and amended on September 3, 1997) in its entirety, including the
exhibits to it.



<PAGE>

                                   SIGNATURES

         Pursuant to the requirements of the Securities Act of 1933, the
registrant certifies that it has reasonable grounds to believe that it meets all
of the requirements for filing on Form S-8 and has duly caused this Registration
Statement to be signed on its behalf by the undersigned, thereunto duly
authorized, in the City of Calgary, Province of Alberta, on August 6, 2004.


                                   NEXEN INC.


                                  By: /s/ John B. McWilliams
                                      --------------------------------
                                      Name:  John B. McWilliams, Q.C.
                                      Title: Senior Vice President, General
                                             Counsel and Secretary


                                POWER OF ATTORNEY

         The officers and directors of Nexen Inc. whose signatures appear
below hereby constitute and appoint John B. McWilliams, a true and lawful
attorney-in-fact, with full powers of substitution and resubstitution, to sign
and execute on behalf of the undersigned any and all amendments, including any
post-effective amendments, to this Registration Statement, and to file the
same, with exhibits thereto, and other documents in connection therewith, with
the Securities and Exchange Commission, and each of the undersigned does
hereby ratify and confirm all that said attorney-in-fact shall do or cause to
be done by virtue thereof.

         Pursuant to the requirements of the Securities Act of 1933, this
Registration Statement has been signed by the following persons in the
capacities indicated effective August 6, 2004:

      Signature                             Title
      ---------                             -----

/s/ Charles W. Fischer      President, Chief Executive Officer and Director
-------------------------   (Principal Executive Officer)
Charles W. Fischer


/s/ Dennis G. Flanagan      Director
-------------------------
Dennis G. Flanagan


/s/ David A. Hentschel      Director
-------------------------
David A. Hentschel


/s/ S. Barry Jackson        Director
-------------------------
 S. Barry Jackson


<PAGE>

      Signature                             Title
      ---------                             -----


/s/ Kevin J. Jenkins        Director
-------------------------
 Kevin J. Jenkins


/s/ Eric P. Newell          Director
-------------------------
  Eric P. Newell, Q.C


/s/ Thomas C. O'Neill       Director
-------------------------
 Thomas C. O'Neill


/s/ Francis M. Saville      Director
-------------------------
 Francis M. Saville, Q.C


/s/ Richard M. Thomson      Director
-------------------------
 Richard M. Thomson, Q.C


/s/ John M. Willson         Director
----------------------
  John M. Willson


/s/ Victor J. Zaleschuk     Director
-------------------------
 Victor J. Zaleschuk


/s/ Marvin F. Romanow       Executive Vice President and Chief Financial Officer
-------------------------   (Principal Financial Officer)
 Marvin F. Romanow


/s/ Michael J. Harris       Controller
-------------------------   (Controller and Principal Accounting Officer)
 Michael J. Harris


<PAGE>

         Pursuant to the requirements of the Securities Act of 1933, the
Administrative Committee of the Nexen Savings Plan has duly caused this
Registration Statement to be signed on its behalf by the undersigned, thereunto
duly authorized, in the City of Dallas, State of Texas, on August 6, 2004.


                               NEXEN SAVINGS PLAN



                               By:  /s/ John M. Glynn
                                    ------------------------------------------
                                    Name:   John M. Glynn
                                    Title:  Member of Administrative Committee



                               By:  /s/ Laurie P. Gupton
                                    ------------------------------------------
                                    Name:   Laurie P. Gupton
                                    Title:  Member of Administrative Committee



                               By:  /s/ Judy K. Williams
                                    ------------------------------------------
                                    Name:   Judy K. Williams
                                    Title:  Member of Administrative Committee


<PAGE>

                            AUTHORIZED REPRESENTATIVE

         Pursuant to the requirements to Section 6(a) of the Securities Act, the
undersigned has signed this Registration Statement solely in the capacity of the
duly authorized representative of the Registrant in the United States on August
6, 2004.


                               Nexen Petroleum U.S.A. Inc.



                               By:  /s/ Douglas B. Otten
                                    -----------------------------------
                                    Douglas B. Otten
                                    President and Chairman of the Board



<PAGE>

                                  EXHIBIT INDEX
                                  -------------

Exhibit                Description
-------                -----------
4.1                    By-Law No. 2 of the Registrant enacted December 9,
                       2003, being a by-law relating generally to the
                       transaction of the business and affairs of the
                       Registrant (filed as Exhibit 3.9 to Form 10-K,
                       filed February 20, 2004 by the Registrant and
                       incorporated by reference herein).

4.2                    Amended and Restated Shareholder Rights Plan
                       Agreement dated May 2, 2002 between the
                       Corporation and CIBC Mellon Trust Company, as
                       Rights Agent, which includes the Form of Rights
                       Certificate as Exhibit A (filed as Exhibit 3 to
                       Form 8-A/A dated August 20, 2002, filed by the
                       Registrant and incorporated by reference herein).

23.1*                  Consent of Deloitte & Touche LLP.

24.1                   Powers of Attorney (included on the signature pages to
                       this registration statement).



*    Filed herewith
[{"type": "S-8", "sequence": "1", "filename": "forms-8.txt", "description": "REGISTRATION STATEMENT - NEXEN SAVINGS PLAN", "secsgml_size_bytes": 11228}]
{"company-data": {"conformed-name": "NEXEN INC", "cik": "0000016873", "assigned-sic": "1311", "irs-number": "986000202", "state-of-incorporation": "A0", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-118019", "film-number": "04958892"}, "business-address": {"street1": "801-7TH AVENUE SW", "city": "CALGARY ALBERTA CANA", "state": "A0", "zip": "T2P 3P7", "phone": "4036994000"}, "mail-address": {"street1": "801-7TH AVENUE SW", "street2": "801-7TH AVENUE SW", "city": "CALGARY ALBERTA CANA", "state": "A0", "zip": "T2P 3P7"}, "former-company": {"former-conformed-name": "CANADIAN OCCIDENTAL PETROLEUM LTD", "date-changed": "19960813"}}
AS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION ON AUGUST 6, 2004
                                                  Registration No: 333-_________

                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                    FORM S-8
             REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933

                                   Nexen INC.
             (Exact name of registrant as specified in its charter)

                  CANADA                                 98-6000202
     (State or other jurisdiction of           (IRS Employer Identification No.)
      incorporation or organization)
                    _________________________________________

                              801 - 7th Avenue S.W.
                        Calgary, Alberta, Canada T2P 3P7
                              Phone: (403) 699-4000
          (Address, including zip code, and telephone number, including
             area code, of registrant's principal executive offices)

                               NEXEN SAVINGS PLAN
                            (Full title of the plan)

                           Nexen Petroleum U.S.A. Inc.
                                12790 Merit Drive
                                    Suite 800
                               Dallas, Texas 75251
                     (Name and address of agent for service)

                                 (972) 450-4600
          (Telephone number, including area code, of agent for service)
                              ____________________
COPIES TO:
John B. McWilliams                        Gregg Radetsky                    Edwin S. Maynard
Senior Vice President, General Counsel    Vice President and General Counsel           Andrew J. Foley
            and Secretary                     Nexen Petroleum U.S.A. Inc.      Paul, Weiss, Rifkind, Wharton &
              Nexen Inc.                           12790 Merit Drive                    Garrison LLP
        801 - 7th Avenue S.W.                          Suite 800                 1285 Avenue of the Americas
   Calgary, Alberta, Canada T2P 3P7               Dallas, Texas 75251           New York, New York 10019-6064
CALCULATION OF REGISTRATION FEE
================================================================================================================
                                                     Proposed Maximum     Proposed Maximum
          Title of                Amount to be        Offering Price     Aggregate Offering       Amount of
 Securities to be Registered     Registered (1)(2)      Per Share (3)            Price         Registration Fee
----------------------------------------------------------------------------------------------------------------
Common Shares, no par value       400,000 shares        $38.06             $15,224,000            $1,929
----------------------------------------------------------------------------------------------------------------
(1)      This Registration Statement also applies to rights under the
         Registrant's Shareholder Rights Plan Agreement, which are attached to
         and tradable only with the common shares registered hereby. No
         registration fees are required for such rights as they will be issued
         for no additional consideration.
(2)      This Registration Statement shall, in accordance with Rule 416 under
         the Securities Act of 1933, as amended, be deemed to cover such
         additional shares as may be issued to prevent dilution resulting from
         stock splits, stock dividends or similar transactions.
(3)      Calculated in accordance with Rule 457(c) and (h)(1) under the
         Securities Act, as amended, and equal to the average of the high and
         low prices reported on the New York Stock Exchange on August 4, 2004, a
         date within five business days of the filing of this Registration
         Statement.
EXPLANATORY NOTE

         We are filing this registration statement for the purpose of
registering, in accordance with General Instruction E of Form S-8, an additional
400,000 Common Shares, no par value, to be issued under the Registrant's Nexen
Savings Plan, formerly known as the CXY Savings Plan. We incorporate by
reference into this registration statement on Form S-8 our previously filed
registration statement on Form S-8, as amended (File No. 033-79666, filed on
June 2, 1994 and amended on September 3, 1997) in its entirety, including the
exhibits to it.
SIGNATURES

         Pursuant to the requirements of the Securities Act of 1933, the
registrant certifies that it has reasonable grounds to believe that it meets all
of the requirements for filing on Form S-8 and has duly caused this Registration
Statement to be signed on its behalf by the undersigned, thereunto duly
authorized, in the City of Calgary, Province of Alberta, on August 6, 2004.

                                   NEXEN INC.

                                  By: /s/ John B. McWilliams
                                      --------------------------------
                                      Name:  John B. McWilliams, Q.C.
                                      Title: Senior Vice President, General
                                             Counsel and Secretary

                                POWER OF ATTORNEY

         The officers and directors of Nexen Inc. whose signatures appear
below hereby constitute and appoint John B. McWilliams, a true and lawful
attorney-in-fact, with full powers of substitution and resubstitution, to sign
and execute on behalf of the undersigned any and all amendments, including any
post-effective amendments, to this Registration Statement, and to file the
same, with exhibits thereto, and other documents in connection therewith, with
the Securities and Exchange Commission, and each of the undersigned does
hereby ratify and confirm all that said attorney-in-fact shall do or cause to
be done by virtue thereof.

         Pursuant to the requirements of the Securities Act of 1933, this
Registration Statement has been signed by the following persons in the
capacities indicated effective August 6, 2004:

      Signature                             Title
      ---------                             -----

/s/ Charles W. Fischer      President, Chief Executive Officer and Director
-------------------------   (Principal Executive Officer)
Charles W. Fischer

/s/ Dennis G. Flanagan      Director
-------------------------
Dennis G. Flanagan

/s/ David A. Hentschel      Director
-------------------------
David A. Hentschel

/s/ S. Barry Jackson        Director
-------------------------
 S. Barry Jackson
Signature                             Title
      ---------                             -----

/s/ Kevin J. Jenkins        Director
-------------------------
 Kevin J. Jenkins

/s/ Eric P. Newell          Director
-------------------------
  Eric P. Newell, Q.C

/s/ Thomas C. O'Neill       Director
-------------------------
 Thomas C. O'Neill

/s/ Francis M. Saville      Director
-------------------------
 Francis M. Saville, Q.C

/s/ Richard M. Thomson      Director
-------------------------
 Richard M. Thomson, Q.C

/s/ John M. Willson         Director
----------------------
  John M. Willson

/s/ Victor J. Zaleschuk     Director
-------------------------
 Victor J. Zaleschuk

/s/ Marvin F. Romanow       Executive Vice President and Chief Financial Officer
-------------------------   (Principal Financial Officer)
 Marvin F. Romanow

/s/ Michael J. Harris       Controller
-------------------------   (Controller and Principal Accounting Officer)
 Michael J. Harris
Pursuant to the requirements of the Securities Act of 1933, the
Administrative Committee of the Nexen Savings Plan has duly caused this
Registration Statement to be signed on its behalf by the undersigned, thereunto
duly authorized, in the City of Dallas, State of Texas, on August 6, 2004.

                               NEXEN SAVINGS PLAN

                               By:  /s/ John M. Glynn
                                    ------------------------------------------
                                    Name:   John M. Glynn
                                    Title:  Member of Administrative Committee

                               By:  /s/ Laurie P. Gupton
                                    ------------------------------------------
                                    Name:   Laurie P. Gupton
                                    Title:  Member of Administrative Committee

                               By:  /s/ Judy K. Williams
                                    ------------------------------------------
                                    Name:   Judy K. Williams
                                    Title:  Member of Administrative Committee
AUTHORIZED REPRESENTATIVE

         Pursuant to the requirements to Section 6(a) of the Securities Act, the
undersigned has signed this Registration Statement solely in the capacity of the
duly authorized representative of the Registrant in the United States on August
6, 2004.

                               Nexen Petroleum U.S.A. Inc.

                               By:  /s/ Douglas B. Otten
                                    -----------------------------------
                                    Douglas B. Otten
                                    President and Chairman of the Board
EXHIBIT INDEX
                                  -------------

Exhibit                Description
-------                -----------
4.1                    By-Law No. 2 of the Registrant enacted December 9,
                       2003, being a by-law relating generally to the
                       transaction of the business and affairs of the
                       Registrant (filed as Exhibit 3.9 to Form 10-K,
                       filed February 20, 2004 by the Registrant and
                       incorporated by reference herein).

4.2                    Amended and Restated Shareholder Rights Plan
                       Agreement dated May 2, 2002 between the
                       Corporation and CIBC Mellon Trust Company, as
                       Rights Agent, which includes the Form of Rights
                       Certificate as Exhibit A (filed as Exhibit 3 to
                       Form 8-A/A dated August 20, 2002, filed by the
                       Registrant and incorporated by reference herein).

23.1*                  Consent of Deloitte & Touche LLP.

24.1                   Powers of Attorney (included on the signature pages to
                       this registration statement).

*    Filed herewith