| Region | Name of Regional Business Unit or Subsidiary | Location |
|---|---|---|
| Japan | Kansai Regional Business Unit | Osaka |
| Chubu Regional Business Unit | Nagoya | |
| Kyushu-Okinawa Regional Business Unit/ Sumitomo Corporation Kyushu Co., Ltd. | Fukuoka | |
| Sumitomo Corporation Hokkaido Co., Ltd. | Sapporo | |
| Sumitomo Corporation Tohoku Co., Ltd. | Sendai | |
| Asia | Sumitomo Corporation (China) Holding Ltd. | Beijing |
| Sumitomo Corporation (China) Limited | Beijing | |
| Sumitomo Corporation (Shanghai) Limited | Shanghai | |
| Sumitomo Corporation (Tianjin) Ltd. | Tianjin | |
| Sumitomo Corporation (Dalian) Ltd. | Dalian | |
| Sumitomo Corporation (Qingdao) Ltd. | Qingdao | |
| Sumitomo Corporation (Guangzhou) Ltd. | Guangzhou | |
| Shenzhen Sumitomo Corporation Ltd. | Shenzhen | |
| Sumitomo Corporation (Hong Kong) Limited | Hong Kong | |
| Sumitomo Corporation Taiwan Ltd. | Taipei | |
| Sumitomo Corporation Korea Ltd. | Seoul | |
| Sumitomo Corporation Asia Pte. Ltd. | Singapore | |
| Sumitomo Corporation Thailand, Ltd. Sumi-Thai International Limited | Bangkok | |
| Sumur Cahaya Sdn. Bhd. | Kuala Lumpur | |
| Sumitomo Corporation of the Philippines | Manila | |
| PT. Sumitomo Indonesia | Jakarta | |
| Sumitomo Corporation Vietnam LLC | Hanoi | |
| Sumitomo Corporation India Private Limited | New Delhi | |
| Oceania | Sumitomo Australia Pty Ltd | Sydney |
| The Middle East | Sumitomo Corporation Middle East FZE | Dubai |
| Sumitomo Corporation Iran, Ltd. | Teheran | |
| Sumitomo Corporation Dis Ticaret A.S. | Istanbul | |
| Europe and CIS | Sumitomo Corporation (Central Eurasia) LLC | Moscow |
| Sumitomo Corporation Europe Holding Limited | London | |
| Sumitomo Corporation Europe Limited | London | |
| Sumitomo Corporation España S.A. | Madrid | |
| Sumitomo Deutschland GmbH | Dusseldorf | |
| Sumitomo France S.A.S. | Paris | |
| Sumitomo Benelux S.A./N.V. | Brussels | |
| North America | Sumitomo Canada Limited | Calgary |
| Sumitomo Corporation of America | New York | |
| Central America and South America |
Sumitomo Corporation de Mexico S.A. de C.V. | Mexico City |
| Sumitomo Corporation del Ecuador S.A. | Quito | |
| Sumitomo Corporation de Venezuela, S.A. | Caracas | |
| Sumitomo Corporation Colombia S.A. | Bogota | |
| Sumitomo Corporation del Peru S.A. | Lima | |
| Sumitomo Corporation Argentina S.A. | Buenos Aires | |
| Sumitomo Corporation (Chile) Limitada | Santiago | |
| Sumitomo Corporation do Brasil S.A. | Sao Paulo |