1. 0 2003 Results Announcement March 23, 2004 China Oilfield Services Limited

2. 1 Overview

3. 2 Summary Highlights  Strong financial performance  Total revenues of RMB3.1 bn, 12.3% yoy growth  Net Income of RMB466 mm, 32% yoy growth  57 exploration and 139 development wells drilled  Fleet expansion  Construction of a 400-feet jackup rig in bidding stage  5 new vessels added to vessel fleet  Strong financial performance  Total revenues of RMB3.1 bn, 12.3% yoy growth  Net Income of RMB466 mm, 32% yoy growth  57 exploration and 139 development wells drilled  Fleet expansion  Construction of a 400-feet jackup rig in bidding stage  5 new vessels added to vessel fleet

4. 3 Summary Financial Results (RMB mm) 20022003% Change Revenues2,726 3,06212.3% Operating Expenses2,247 2,52412.3% EBITDA1,072 1,20812.7% EBIT483 55013.8% Net Income354 46631.5% EBITDA Margin39.3%39.5% EBIT Margin17.7%18.0% Net Margin13.0%15.2% EPS (RMB cents)12.84 11.66

5. 4  Revenues of drilling and geophysical segment grew more than 20% respectively in 2003  Higher drilling rig day rates and higher jackup utilization  Higher job volume for 3D seismic data collection  Continuous growth of marine support and transportation segment  Revenues of drilling and geophysical segment grew more than 20% respectively in 2003  Higher drilling rig day rates and higher jackup utilization  Higher job volume for 3D seismic data collection  Continuous growth of marine support and transportation segment Growth by Segments 2003 Revenue by Segment 99-03 Revenue CAGR of 16.5% 2002-2003 Growth DrillingMarine Support & TransportationWell ServicesGeophysical 20% 5% 23% Marine Support & Transportation 21%

6. 5 Cost Breakdown Operating Expenses SG&A and Others Higher provision for bad debt Depreciation Asset re-valuation before IPO Addition of 5 new vessels and other equipment Consumption of supplies and others Increase in business volume for drilling and geophysical segments (1)Includes other operating expenses, provision for impairment of long term investments and provision for impairment of property, plant and equipment Depreciation of property, plant and equipment Repair and maintenance costs Consumption of supplies, materials, fuel, services and others Employee compensation costs Operating lease expenses Other SG&A and others (1) (RMB mm) 13% 11% 8% 11% 98% 9% Employee compensation Mainly due to increase in business volume Repair and maintenance Increased repair and maintenance of drilling rigs Operating lease expenses More lease of equipment for well services Lease of more convoy vessels for geophysical services 2,247 2,524

7. 6 PRC Tax Rate and Tax Refund  Normal PRC corporate tax rate of 33%  COSL was registered in Sept 2002 at Tianjin Tanggu Marine Hi-New Tech Development Zone, and qualified as an “Advanced Technology Enterprise” with preferential tax treatment  We have applied to qualify for this corporate income tax incentive program for fiscal year 2003  For conservativeness reason, 2003 income tax provisions were made based on 33% corporate tax rate  Normal PRC corporate tax rate of 33%  COSL was registered in Sept 2002 at Tianjin Tanggu Marine Hi-New Tech Development Zone, and qualified as an “Advanced Technology Enterprise” with preferential tax treatment  We have applied to qualify for this corporate income tax incentive program for fiscal year 2003  For conservativeness reason, 2003 income tax provisions were made based on 33% corporate tax rate

8. 7 Capital Expenditure - Actual vs. Budget Capital Expenditure DrillingMarine Support & TransportationWell ServicesGeophysical % of budget ~80% ~90%

9. 8 Capital Expenditures Marine Support & Transportation and Well Services segments accounted for the majority of capital expenditures in 2003 Capital Expenditures DrillingWell Services Marine Support & Transportation Geophysical  Drilling:  Of the total RMB222 mm, ~RMB80 mm was spent on maintenance and upgrade of BH7 and NH5  Well services:  Of the total RMB366 mm, ~RMB125 mm was spent on the purchase of logging and directional drilling equipment  Marine support & transportation  Mainly for vessel construction  Geophysical:  Mainly for equipment purchase, maintenance and upgrades  Drilling:  Of the total RMB222 mm, ~RMB80 mm was spent on maintenance and upgrade of BH7 and NH5  Well services:  Of the total RMB366 mm, ~RMB125 mm was spent on the purchase of logging and directional drilling equipment  Marine support & transportation  Mainly for vessel construction  Geophysical:  Mainly for equipment purchase, maintenance and upgrades (1) (1)Incl. cash payment of RMB1,114 mm and committed letter of credit of RMB142 mm

10. 9 Strong Balance Sheet RMB MM2002%2003% Cash and Cash Equivalents2,63233%2,19927% Accounts Receivable5257%5687% Other Current Assets3434%4886% PP&E4,31754%4,82759% JV's & Others1412%1492% Total Assets7,958100%8,231100% Short-term Loan00%0 Trade Payables and Other Payables2753%2863% Other Current Liabilites3354%2593% Long-term Loan00%0 Deferred Tax Liability5677%5417% Long-term Payable to CNOOC6008%6007% Total Liabilites1,77722%1,68620% Shareholders' Equity6,18178%6,54580% Total Liabilities and Shareholders' Equity7,958100%8,231100%

11. 10 Dividend  Board of Directors proposed a year-end dividend of RMB2.27 cents per share  Subject to annual general meeting to approve  2003 annual dividend of RMB3.5 cents per share (incl. RMB1.23 cents special interim dividend and RMB2.27 cents year-end dividend per share)  30% payout of 2003 annual net income  1.3% (1) dividend yield  Consistent with dividend policy  Board of Directors proposed a year-end dividend of RMB2.27 cents per share  Subject to annual general meeting to approve  2003 annual dividend of RMB3.5 cents per share (incl. RMB1.23 cents special interim dividend and RMB2.27 cents year-end dividend per share)  30% payout of 2003 annual net income  1.3% (1) dividend yield  Consistent with dividend policy (1) Based on closing share price of HK$2.625 as of Mar.19, 2004

12. 11 Segment Analysis

13. 12 A.Drilling

14. 13 Well Workover Trends Summary Drilling Activity Number of development wells drilled in 2003 doubled that of 2002 Summary Drilling Activity

15. 14 Utilization and Day Rates Source: COSL, ODC (utilization based on days available) Jackup WTI (US$/bbl) Utilization Semi WTI (US$/bbl) Utilization COSLGlobalWTI Utilization Rates Source: COSL, ODC (Jackup day rates for 300’ rigs) (US$/day) Comparative Day Rates GOMCOSL West Africa SE Asia  Strong domestic demand and international deployment continue to drive up average day rates  Jackup utilization continued to surpass international peers; semi- submersible utilization was lower in 2003, but expected to improve in 2004

16. 15 Segment Financial Performance Drilling Turnover YoY growth = 21% Note:2003 drilling revenue includes all well workover revenues 1,064 1,283 Operating Profit and Margin YoY Op. Profit growth = 5%  Higher day rates and utilization of jackup rigs drove segment revenue growth  Operating profit increased 5% yoy while margin decreased partially due to lower semi-submersible utilization rate  Higher day rates and utilization of jackup rigs drove segment revenue growth  Operating profit increased 5% yoy while margin decreased partially due to lower semi-submersible utilization rate

17. 16 B.Well Services

18. 17 Business Unit Contribution Well Services Revenue Breakdown Well Services Job Breakdown  Significant growth of directional drilling business due to large number of development wells offshore China and deployment of one more LWD system  Operating challenges for other well services business units  Change of exploration strategy of E&P companies reduced the number of logging trips required  Lack of high margin HTHP wells lowered cementing revenues despite higher business volume  Significant growth of directional drilling business due to large number of development wells offshore China and deployment of one more LWD system  Operating challenges for other well services business units  Change of exploration strategy of E&P companies reduced the number of logging trips required  Lack of high margin HTHP wells lowered cementing revenues despite higher business volume

19. 18 Segment Financial Performance Well Services Revenues Operating Profit and Margin YoY Op. Profit growth = 20%  Despite total well services revenue being flat at RM673 million in 2003, we achieved 20% yoy increase in operating profit and improved margin thanks to effective cost management

20. 19 C.Marine Support and Transportation

21. 20 Fleet Growth and Capacity Expansion Fleet Growth Operating Days 60 63 54  One utility vessel and one oil tanker were disposed in 2003  One AHTS and four standby vessels commenced service Continuous capacity expansion to meet increasing demand

22. 21 Higher and More Stable Utilization Compared to Global Peers Note:Trico Marine and Seacor Smit calculate their respective utilization rates based on calendar day utilization methodology; Tidewater and Gulfmark calculate their respective utilization rates based on availability utilization methodology. Tidewater, Seacor Smit, and Gulfmark 03 utilization rate is the average for the 9 months ended Sep 30, 2003 Calendar Day Utilization Rate Availability Utilization Rate Constantly higher than peer and more stable vessel utilization due to strong demand in offshore China

23. 22 Segment Financial Performance  Revenue growth driven by higher day rates and number of operating days  Lower operating profit margin mainly due to higher depreciation as a result of IPO revaluation and additional depreciation from new vessels in service  Revenue growth driven by higher day rates and number of operating days  Lower operating profit margin mainly due to higher depreciation as a result of IPO revaluation and additional depreciation from new vessels in service Revenues YoY growth = 4.9% Operating Profit and Margin YoY Op. Profit growth = -29%

24. 23 D.Geophysical

25. 24 Seismic Collection 2D Seismic Collection (km) 3D Seismic Collection (km 2 )  Overseas 2D seismic collection volume increased by 6%  NH 502 in West Africa and BH 512 at Gulf of Mexico for 2D seismic collection  25% increase in 3D seismic collection volume and higher price  Overseas 2D seismic collection volume increased by 6%  NH 502 in West Africa and BH 512 at Gulf of Mexico for 2D seismic collection  25% increase in 3D seismic collection volume and higher price 48,422 46,737

26. 25 Geophysical Revenues YoY growth = 23% Operating Profit and Margin YoY Op. Profit growth = 575%  Geophysical revenues yoy growth of 23% mainly driven by strong demand for 3D seismic data collection services offshore China  Increased business volume and operating efficiency significantly improved operating profit and margins  Geophysical revenues yoy growth of 23% mainly driven by strong demand for 3D seismic data collection services offshore China  Increased business volume and operating efficiency significantly improved operating profit and margins

27. 26 Integrated Project Management (“IPM”)  Total of 9 IPM projects contracted in 2003, accounting for 14% of 2003 total turnover  Integration facilitates the margin and growth of non-drilling segments  Total of 9 IPM projects contracted in 2003, accounting for 14% of 2003 total turnover  Integration facilitates the margin and growth of non-drilling segments IPM Revenue Contribution YoY Revenue growth = 74% ShippingDrilling Well Services Drilling Turnkey Drilling: Drilling & Well Services Well Srvce. DrillingGeophy.Shipping Drilling Well Services Shipping IPM Programs

28. 27 2004 Outlook

29. 28 Robust Drilling Activities Expected Source: Company Eastern South China Sea Bohai Bay East China Sea Western South China Sea Characteristics of Development Wells  Subject to development schedules rather than exploration uncertainties  Number of wells required varies by region – greater in Bohai Bay  Development well programs typically lead to more stable and predictable demand for various oilfield services 2004E 60 - 70 199719981999200020012002 26 34 25 27 24 56 31 161 117 134 66 57 139 57 2003 180+ ~250

30. 29 Planned Capital Expenditures  Drilling:  Construction of a 400-feet jackup rig  Current drilling fleet upgrade and maintenance  Well services:  Technology upgrade through internal R&D and external equipment purchase  Marine support & transportation  Construction of 11 vessels  Geophysical:  Construction of a new survey vessel  Current fleet upgrade  Drilling:  Construction of a 400-feet jackup rig  Current drilling fleet upgrade and maintenance  Well services:  Technology upgrade through internal R&D and external equipment purchase  Marine support & transportation  Construction of 11 vessels  Geophysical:  Construction of a new survey vessel  Current fleet upgrade 2004 Planned Capital Expenditures Total = RMB1.7 bn 2004 Capex program will focus on capacity expansion to meet growing offshore China demand

31. 30 THANK YOU www.cosl.com.cn