| 1853 | Ishikawajima Shipyard is established. |
| 1876 | Ishikawajima Hirano Shipyard is established. |
| 1889 | Ishikawajima Shipbuilding & Engineering Co., Ltd. is established. |
| 1907 | Harima Dock Co., Ltd. is established (subject to a merger later on). |
| 1924 | Ishikawajima Aircraft Manufacturing Co., Ltd. is established (becomes TACHIHI ENTERPRISE CO.,Ltd.and New Tachikawa Aircraft Co., Ltd. later on). |
| 1929 | The automobile section spins off and Ishikawajima Automotive Works Co., Ltd. is established (becomes Isuzu Motors Limited later on through a series of mergers). Harima Dock Co., Ltd. is renamed to Harima Shipbuilding & Engineering Co., Ltd. |
| 1936 | Ishikawajima Shibaura Turbine Co., Ltd. is established (for manufacturing of steam turbines for use on land) jointly with Shibaura Engineering Works Co., Ltd. (currently Toshiba Corporation). |
| 1939 | Shibaura United Engineering Co., Ltd. is established jointly with Shibaura Engineering Works Co., Ltd. (currently Toshiba Corporation) and United Engineering & Foundry (USA). |
| 1941 | Nagoya Shipbuilding Co., Ltd. is established (subject to a merger later on) |
| 1945 | Ishikawajima Hirano Shipyard established Ishikawajima Heavy Industries Co., Ltd. after changing its name twice. |
| 1954 | Kure Dock splits off from Harima Shipbuilding & Engineering Co., Ltd. and is established as Kure Shipbuilding & Engineering Co., Ltd. |
| 1957 | Tanashi Aero-Engine Plant opens as a factory specializing in jet engines. |
| 1959 | ISHIBRAS is established. |
| 1960 | Ishikawajima Heavy Industries Co., Ltd. and Harima Shipbuilding & Engineering Co., Ltd. merge to establish Ishikawajima-Harima Heavy Industries Co., Ltd. (IHI) |
| 1961 | Accompanying merger and acquisition of Ishikawajima Shibaura Turbine Co., Ltd. by Toshiba Corporation, Ishikawajima-Shibaura Seiki Co., Ltd. is established (subject to a merger later on). Nagoya Heavy Industries Co., Ltd. is established (subject to a merger later on). |
| 1962 | Merges with Ishikawajima-Shibaura Seiki Co., Ltd. and Shibaura Sewing Machine Co., Ltd. (capital: 15.4 billion yen) |
| 1964 | Yokohama No.1 Works (currently Yokohama Machinery Works) is established as a heavy machinery plant. Merges with Nagoya Shipbuilding Co., Ltd. and Nagoya Heavy Industries Co., Ltd. (capital: 24 billion yen). Yokohama No.2 Works (currently IHI Marine United Yokohama Shipyard) is established as a shipbuilding plant (operation on the first ship starts on October 22). |
| 1967 | Merges with Shibaura United Enginering (capital: 25.872 billion yen). |
| 1968 | First term of Yokohama No.3 Works (currently Yokohama Nuclear & Chemical Components Works), or a heavy container works, is completed. Merges with Kure Shipbuilding & Engineering Co., Ltd. (capital: 28.872 billion yen). |
| 1973 | Chita Works (currently Aichi Works) opens. |
| 1981 | Japanese Aero Engines Corporation is established (jointly by Mitsubishi Heavy Industries, Ltd. and Kawasaki Heavy Industries, Ltd.). |
| 1983 | International Aero Engines is established through development of civil aircraft engines (V2500) by Japan, England, the United States, Germany, and Italy. |
| 1988 | The diesel engine department spins off for establishment of Diesel United, Ltd. |
| 1994 | Construction of "Yokohama Engineering Center" is completed. |
| 1995 | Marine United is established jointly with Sumitomo Heavy Industries, Ltd. |
| 1998 | Construction of Soma Aero-Engine Plant as a jet engine parts plant is completed. |
| 2000 | IHI Aerospace Co. Ltd, established to take over the aerospace business of Nissan Motor Co., Ltd., starts operation. |
| 2001 | The paper manufacturing machine section spins off for establishment of Voith IHI Paper Technology Co., Ltd. jointly with Voith (Germany). |
| 2002 | Construction of "Yokohama Engineering Center 2" is completed. Shipbuilding & Offshore Operations becomes a separate corporation, IHI Marine United Inc. |
| 2003 | Taking over the "engines and turbines" business and "transportation system, vehicle, and snowplows" business, Niigata Power Systems Co., Ltd. and Niigata Transys Co., Ltd. are established. The space development business is integrated into IHI Aerospace Co., Ltd. |
| 2004 | Joint machinery companies are successively established in China jointly with local manufacturers. "Changchun FAWER-IHI Turbo Co., Ltd." for vehicle turbochargers "Hangzhou XIZI-IUK Parking System Co., Ltd." for mechanical parking systems (Ishikawajima Transport Machinery Co., Ltd.) "IHI-Sullair Compression Technology (Suzhou) Co., Ltd." for general-purpose compressors |
| 2005 | IHI METALTECH Co., Ltd., rolling milling subsidiary, is established as a joint venture with VOEST-ALPINE Industrie-anlagenbau GmbH & Co of Austria. |
| 2006 | Head Office is relocated to Toyosu, Koto-ku, Tokyo (Toyosu IHI Building). |
| 2007 | The company name is changed from "Ishikawajima-Harima Heavy Industries Co., Ltd" to "IHI Corporation". |