press release

Unocal's 4Q 2004 earnings conference call set for Feb. 1; presentation at CSFB Energy Summit on Feb. 2

El Segundo, Calif., Jan 25, 2005 -- Unocal Corporation (NYSE: UCL) will discuss its fourth quarter 2004 financial and operating results in a conference call webcast on Unocal's web site on Tuesday, Feb. 1, 2005. The conference call will begin at 1 p.m. PST (4 p.m. EST).

Charles R. Williamson, Unocal's chairman and chief executive officer, will also present a company update at the CSFB Energy Summit on Feb. 2, 2005, at 7:15 a.m. PST (10:15 a.m. EST). This will presentation will also be webcast on Unocal's web site.

4Q earnings conference call

Investors, analysts, news media, employees and the general public are invited to listen to the 4Q earnings conference call webcast by visiting the Unocal web site (www.unocal.com) and clicking on the conference call banner on the home page or by clicking on the "News and Presentations" link in the Investor Relations section of the Unocal web site. In addition, graphics of the slides (pdf format) referenced during the call will be available for viewing on-line or downloading from the Investor Relations section of the web site.

Replays of the audio conference call will be available through Mar. 4, 2005. Transcripts of the conference call and the graphic files will be archived.

Robert E. Wright, vice president of Investor Relations for Unocal, will be the conference call moderator. Charles R. Williamson, Unocal chairman and chief executive officer; Joseph H. Bryant, Unocal president and chief operating officer; and Terry G. Dallas, Unocal executive vice president and chief financial officer, will also participate in the call.

Unocal expects to issue a new release on its fourth quarter 2004 earnings results on Feb. 1 prior to the open of trading on the NYSE. This news release will be available on the Unocal web site and furnished with the Securities and Exchange Commission on Form 8-K.

CSFB Energy Summit presentation

Unocal will also webcast a company update presentation by Williamson at the CSFB Energy Summit on Feb. 2, 2005, at 7:15 a.m. PST (10:15 a.m. EST).

The presentation is expected to include information concerning Unocal's recent financial and operating results and the outlook regarding certain exploration, development and production activities.

A live webcast of the presentation, along with slides (in pdf format for viewing on-line or downloading), will be available on Unocal's web site, www.unocal.com. Replays of the webcast will be available for 24 hours following the live presentation. A transcript of the presentation and slides will be archived on the web site.

Listeners can access the webcast and slides by clicking on the "News and Presentations" link in the Investor Relations section of the Unocal web site.

About Unocal Corporation

Unocal is one of the world's leading independent natural gas and crude oil exploration and production companies. The company's principal oil and gas activities are in Asia and North America.

Updated: January 2005