EXHIBIT 32.2
                                                                   ------------


CERTIFICATION OF PERIODIC REPORT

In connection with the Amendment No. 1 to the Annual Report on Form 10-K of the
Company for the year ended  December 31, 2005 as filed with the  Securities and
Exchange Commission on February 23, 2006 (as amended, the "Report"),  I, Marvin
F. Romanow, Executive Vice President and Chief Financial Officer of Nexen Inc.,
a Canadian Corporation (the "Company"),  certify, pursuant to 18 U.S.C. Section
1350 as adopted  pursuant  to Section  906 of the  Sarbanes-Oxley  Act of 2002,
that:

(1)   the Report fully complies with the requirements of Section 13(a) or 15(d)
      of the Securities Exchange Act of 1934 (15 U.S.C. 78m or 78o(d)); and

(2)   the information  contained in the Report fairly presents, in all material
      respects,  the  financial  condition  and  results of  operations  of the
      Company.


Date: April 2, 2007                             /s/ Marvin F. Romanow
                                                -------------------------------
                                                Marvin F. Romanow
                                                Executive Vice President, and
                                                Chief Financial Officer




A signed  original of this written  statement  required by Section 906 has been
provided to Nexen Inc. and shall be retained by Nexen Inc. and furnished to the
Securities and Exchange Commission or its staff upon request.