Steel Business Division
| Company Name | Main Business | Country of Operation |
|---|---|---|
 Isuzu Corporation |
Steel processing and sales | Japan |
| Keiyo Blanking Kogyo Co., Ltd. | Steel (thick plates) processing and sales | Japan |
| Kyushu Steel Center Co., Ltd. |
Steel (thick plates) processing | Japan |
| Kyushu Steel Corporation | Steel (building materials) manufacturing | Japan |
| MC Metal Service Asia (Thiland) Co., Ltd. | Steel processing and sales | Thailand |
| Metal One Corporation |
Steel products operations | Japan |
| Metal One Holdings America, Inc. | Holding company of steel processing and sales business | U.S.A. |
| Metal One Ryowa Corporation |
Steel processing and sales | Japan |
| Metal One Specialty Steel Corporation |
Special steel processing and sales | Japan |
| Metal One SSS West Japan, Ltd. |
Steel (building materials) processing and sales | Japan |
| Metal One Stainless (Asia) Pte.Ltd. | Steel (stainless) processing and sales | Singapore |
| Metal One Steel Service Corporation | Steel processing and sales | Japan |
| Metal One Structural Steel & Resource Corporation |
Steel (building materials) processing and sales | Japan |
| M.O.TEC CORPORATION |
Construction materials rentals and sales | Japan |
| Siam Hi-Tech Steel Center Co., Ltd. | Steel processing and sales | Thailand |
| Solutions Usiminas | Steel processing and sales | Brazil |
| Sus-Tech Corporation |
Steel (stainless) processing and sales | Japan |
| Tamatsukuri Corporation |
Steel (thick plates) processing and sales | Japan |
Ferrous Raw Materials Division
| Company Name | Main Business | Country of Operation |
|---|---|---|
| Compania Minera del Pacifico S.A. | Iron ore production and sales | Chile |
| Hernic Ferrochrome (Pty) Ltd. | Mining of chrome ore, production and sales of ferrochrome | Republic of South Africa |
| Iron Ore Company of Canada |
Iron ore production and sales | Canada |
| M.C. Inversiones Limitada | Investment company for iron ore mines in Chile | Chile |
| Mitsubishi Development Pty Ltd | Investment, production and sales of coals and other metals resources | Australia |
Non-Ferrous Metals Division
| Company Name | Main Business | Country of Operation |
|---|---|---|
| JECO Corporation | Investment company for Escondida copper mine in Chile | Japan |
| JECO 2 Ltd. | Investment company for Escondida copper mine in Chile | U.K. |
| Mitsubishi Corporation Unimetals Ltd. |
Metal trading company | Japan |
| NIKKEI MC ALUMINIUM Co., Ltd. |
Manufacturing and sales of secondary aluminum alloy ingots | Japan |
| MC Copper Holdings B.V. | Investment company for Los Pelambres copper mine in Chile | The Netherlands |
| Mozal S.A.R.L. | Production and sale of aluminium ingots | Mozanbique |
| Ryowa Development Pty., Ltd. | Investment company for BOYNE aluminum smelter and sales of aluminum | Australia |
| Ryowa Development II Pty., Ltd. | Investment company for BOYNE aluminum smelter and sales of aluminum | Australia |
| Triland Metals Ltd. | Commodity broker on the London Metal Exchange (LME) | U.K. |
