EXHIBIT 8.1 SUBSIDIARIES OF PETROCHINA COMPANY LIMITED I. WHOLLY-OWNED SUBSIDIARIES 1. Daqing Oilfield Limited Company 2. PetroChina Marketing Company Limited 3. PetroChina International Limited II. CONTROLLED SUBSIDIARIES 1. China National United Oil Corporation 2. Dalian West Pacific Petrochemical Company 3. Beijing Gas Transmission Company 4. Liaohe Jinma Oilfield Company Limited 5. Jilin Chemical Industrial Company Limited 6. Jinzhou Petrochemical Limited Company 7. Gansu Tri-Star Petrochemical Group Company Limited 8. Petroleum Long Champ (Group) Company Limited 9. PetroChina International Co., Ltd. 1 BRANCH COMPANIES AND RESEARCH INSTITUTES UNDER PETROCHINA'S DIRECT CONTROL 1. PetroChina Exploration & Production Company 2. PetroChina Refining & Marketing Company 3. PetroChina Chemicals & Marketing Company 4. PetroChina Natural Gas & Pipeline Company 5. PetroChina Liaohe Oilfield Company 6. PetroChina Jilin Oilfield Company 7. PetroChina Dagang Oilfield Company 8. PetroChina Huabei Oilfield Company 9. PetroChina Changqing Oilfield Company 10. PetroChina Xinjiang Oilfield Company 11. PetroChina Southwest Oil & Gasfield Company 12. PetroChina Qinghai Oilfield Company 13. PetroChina Tarim Oilfield Company 14. PetroChina Tuha Oilfield Company 15. PetroChina Yumen Oilfield Company 16. PetroChina Jidong Oilfield Company 17. PetroChina Zhejiang Exploration Company 18. PetroChina Daqing Petrochemical Company 19. PetroChina Fushun Petrochemical Company 20. PetroChina Liaoyang Petrochemical Company 21. PetroChina Lanzhou Petrochemical Company 22. PetroChina Urumqi Petrochemical Company 23. PetroChina Jilin Petrochemical Company 24. PetroChina Ningxia Petrochemical Company 25. PetroChina Dalian Petrochemical Company 26. PetroChina Jinzhou Petrochemical Company 27. PetroChina Jinxi Petrochemical Company 28. PetroChina Harbin Petrochemical Company 29. PetroChina Qian'guo Petrochemical Company 30. PetroChina Dushanzi Petrochemical Company 31. PetroChina Daqing Refining & Petrochemical Company 32. PetroChina Dagang Petrochemical Company 33. PetroChina North China Petrochemical Company 34. PetroChina Hohhot Petrochemical Company 35. PetroChina North China Chemicals & Marketing Company 36. PetroChina East China Chemicals & Marketing Company 37. PetroChina Northeast Chemicals & Marketing Company 38. PetroChina Northwest Chemicals & Marketing Company 39. PetroChina Lubricant Company 40. PetroChina Northwest Marketing Company 41. PetroChina Northeast Marketing Company 42. PetroChina Southwest Marketing Company 43. PetroChina East China Marketing Company 44. PetroChina North China Marketing Company 45. PetroChina Heilongjiang Marketing Company 2 46. PetroChina Jilin Marketing Company 47. PetroChina Liaoning Marketing Company 48. PetroChina Dalian Marketing Company 49. PetroChina Inner Mongolia Marketing Company 50. PetroChina Ningxia Marketing Company 51. PetroChina Gansu Marketing Company 52. PetroChina Shaanxi Marketing Company 53. PetroChina Qinghai Marketing Company 54. PetroChina Xinjiang Marketing Company 55. PetroChina Sichuan Marketing Company 56. PetroChina Chongqing Marketing Company 57. PetroChina Tibet Marketing Company 58. PetroChina Dalian Marine Shipping Company 59. PetroChina Pipeline Company 60. PetroChina North China Natural Gas & Pipeline Company 61. PetroChina Liaohe Petrochemical Company 62. PetroChina Karamay Petrochemical Company 63. PetroChina Changqing Petrochemical Company 64. PetroChina Daqing Chemicals & Marketing Center 65. PetroChina Fushun Chemicals & Marketing Center 66. PetroChina Liaoyang Chemicals & Marketing Center 67. PetroChina Ningxia Chemicals & Marketing Center 68. PetroChina Dushanzi Chemicals & Marketing Center 69. PetroChina Urumqi Chemicals & Marketing Center 70. PetroChina Lanzhou Chemicals & Marketing Center 71. PetroChina Jilin Chemicals & Marketing Center 72. PetroChina West-East Gas Pipeline Company 73. PetroChina Exploration & Development Research Institute 74. PetroChina Planning & Engineering Institute 3