Natural Gas Business Division A
| Company Name | Main Business | Country of Operation |
|---|---|---|
| Brunei LNG Sendirian Berhad | Manufacturing and sales of LNG | Brunei |
| Brunei Shell Tnakers Sendirian Berhad | Ownership of LNG tankers | Brunei |
| Cordova Gas Resources Ltd. | Development and production of shale gas in Canada | Canada |
| Diamond Gas Resources Pty. Ltd. | Sales agent of JALP crude oil and condensate | Australia |
| Japan Australia LNG (MIMI) Pty. Ltd. | Development and sales of resources (LNG, LPG, condensate and crude oil) | Australia |
Natural Gas Business Division B
| Company Name | Main Business | Country of Operation |
|---|---|---|
| Diamond Gas Sakhalin B.V. | Stockholding company for Sakhalin II project in Russia | The Netherlands |
Petroleum Business Division
| Company Name | Main Business | Country of Operation |
|---|---|---|
| Diamond Tanker Pte. Ltd. | Marine transportation, etc. | Singapore |
 MC Energy, Inc. |
Marketing and sales of asphalt and petroleum products | Japan |
| Mitsubishi Shoji Sekiyu Co., Ltd. |
Marketing and sales of petroleum products | Japan |
| Onahama Petroleum Co., Ltd. |
Oil import, storage and sales as well as land and facility leasing | Japan |
| Pacific Orchid Shipping S.A. | Ownership of tankers for transporting crude and heavy oil | Pnanma |
| Petro-Diamond Inc. |
Marketing and sales of petroleum products | U.S.A. |
| Petro-Diamond Singapore (Pte) Ltd. | Marketing and sales of petroleum products | Singapore |
Carbon & LPG Business Division
| Company Name | Main Business | Country of Operation |
|---|---|---|
| Astomos Energy Corporation |
Import, trading, domestic distribution and sales of LPG | Japan |
Africa, Europe and America E&P Business Unit
| Company Name | Main Business | Country of Operation |
|---|---|---|
| Ajoco Exploration Co., Ltd. | Development and production of oil in Angola | Japan |
| Ajoco'91 Exploration Co., Ltd. | Development and production of oil in Angola | Japan |
| Angola Japan Oil Co., Ltd. | Exproration, development and production of oil in Angora | Japan |
| MCX Exploration (USA), Ltd. | Exploration, development and production of oil and natural gas | U.S.A. |
| MPDC Gabon Co., Ltd. | Exproration, development and production of oil in Gabon | Japan |
Asia E&P Business Unit
| Company Name | Main Business | Country of Operation |
|---|---|---|
| ENCORE ENERGY PTE. Ltd. | Stockholding company for P.T. Medco Energi Internasional | Singapore |
| Energi Mega Pratama Inc. | Exploration, development, and production of oil and natural gas in Indonesia | Indonesia |
