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[MISSION RESOURCES LOGO]

                                                   Mission Resources Corporation
                                                          1331 Lamar, Suite 1455
                                                       Houston, Texas 77010-3039

                                                                    NEWS RELEASE
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Contact:      Ann Kaesermann
              Vice President - Accounting & Investor Relations, CAO
              investors@mrcorp.com
              (713) 495-3100

               Mission Resources to Appeal Nasdaq Delisting Notice

HOUSTON--February 3, 2003--Mission Resources Corporation (Nasdaq: MSSN)
announced today that it has requested a hearing before a Nasdaq Listing
Qualifications Panel to appeal an earlier Nasdaq Staff Determination to delist
the Company's common stock from The Nasdaq National Market.

Mission Resources received a Nasdaq Staff Determination on January 28, 2003,
indicating that the Company had failed to comply with Nasdaq's minimum bid price
requirement of $1.00 per share for continued listing of the Company's common
stock on The Nasdaq National Market as set forth in Nasdaq Marketplace Rule
4450(a)(5). As a result, the Company's common stock is subject to delisting from
The Nasdaq National Market at the opening of business on February 6, 2003.
Following procedures set forth in the Nasdaq Marketplace Rule 4800 Series, the
Company has requested an oral hearing before a Nasdaq Listing Qualifications
Panel to review the Nasdaq Staff Determination. While the date for the hearing
has not yet been established, hearings typically occur within 45 days of a
company's request. The hearing request will stay the delisting of the Company's
common stock, pending the Panel's decision, allowing it to continue to trade on
The Nasdaq National Market under the symbol "MSSN." The Company intends to
present a comprehensive plan to the Nasdaq Listing Qualifications Panel for
achieving and sustaining compliance with the Nasdaq Marketplace Rules, but there
can be no assurance that the Panel will grant the Company's request for
continued listing.

Mission Resources Corporation is a Houston-based independent exploration and
production company that acquires, develops and produces crude oil and natural
gas in the Permian Basin of West Texas, along the Texas and Louisiana Gulf Coast
and in the Gulf of Mexico.

This press release contains "forward-looking statements" within the meaning of
Section 27A of the Securities Act of 1933, as amended, and Section 21E of the
Securities Exchange Act of 1934, as amended. These forward-looking statements
are subject to certain risks, trends and uncertainties that could cause actual
results to differ materially from those projected. Among those risks, trends and
uncertainties are our estimate of the sufficiency of our existing capital
sources, our ability to raise additional capital to fund cash requirements for
future operations, the uncertainties involved in estimating quantities of proved
oil and natural gas reserves, in prospect development and property acquisitions
and in projecting future rates of production, the timing of development
expenditures and drilling of wells, and the operating hazards attendant to the
oil and gas business. In particular, careful consideration should be given to
cautionary statements made in the various reports the Company has filed with the
Securities and Exchange Commission. The Company undertakes no duty to update or
revise these forward-looking statements.