press release

Unocal completes common stock repurchase program

El Segundo, Calif., Aug. 31, 2004 - Unocal Corporation (NYSE: UCL) today said it has completed its previously announced program for the repurchase of Unocal common stock.

The company repurchased 4.13 million common shares for $149.9 million in open market transactions. The average purchase price, including commissions, was $36.30 per share.

The repurchase of Unocal common stock was one aspect of a three-part cash expenditure program of up to $511 million that Unocal announced in late July 2004.

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 operations are in North America and Asia.

Updated: August 2004