COSL Announced Unaudited Operational Data for 1H 2005

[26 July 2005 Hong Kong] China Oilfield Services Limited ( COSL or the Company ; stock code: 2883), the leading oilfield services provider in China offshore market, announced today its unaudited operations statistics for the 6 months ended 30 June 2005.

During the first half of 2005, market demand for drilling services remained strong. For the six months ended 30 June 2005, the total number of wells drilled amounted to 113, of which 87 were development wells and 26 were exploration wells. Total number of operating days was 2,278 days, 22 days less than the same period last year.

It was mainly due to the number of maintenance days, which increased by 184 days from that in the corresponding period the previous year to 235 days during the review period. Average utilization rate of rigs reached 99.1%. The Company operated for 4,073 team/days for its well workover business and achieved an encouraging growth of 20%.

During the period, operating datum of well services for which the Company provided logging, drilling fluids, directional drilling, cementing and well completion services were 342, 174, 95, 122 and 508 respectively.

The Company s marine support and transportation services business recorded impressive growth during the period. The Company s marine support vessels operated for a total of 11,444 days, an increase of 949 days or 9% as compared with that for the same period the previous year. Average utilization rate was in line with that in the previous year, reaching 98.2%.

Regarding the geophysical services, the Company s collection of 2D and 3D seismic data increased by 7% and 62% respectively, while the processing of 2D and 3D seismic data decreased by 35% and 2% respectively.

Commenting on the operational data, Mr. Yuan Guangyu, CEO and President of COSL, said, As the major integrated oilfield services provider in offshore China, we achieved satisfactory growth amidst favorable operating environment. We have full confidence in achieving remarkable performance in our full-year results.

Operational Performance Overview: