| July 1948 |
Established Japan Power Welding Machine Co., Ltd. |
| March 1959 |
Developed and manufactured high-speed engine-driven welders |
| December 1961 |
Completed construction on Saitama plant and began to manufacture engine-driven generators |
| February 1966 |
Developed sound-proof generators and began production of sound-proof engine-driven generators and welders |
| July 1966 |
Changed its corporate name to Denyo Co., Ltd. |
| July 1970 |
Completed construction on Shiga plant |
| April 1973 |
Began to manufacture engine-driven air compressors |
| March 1976 |
Established joint venture, P.T. Denyo Indonesia (currently P.T. Dein Prima Generator) |
| April 1976 |
Completed construction on Fukui plant |
| February 1983 |
Denyo was listed on Second Section of the Tokyo Stock Exchange |
| December 1992 |
Established U.S. subsidiary, Denyo America Corporation |
| August 1995 |
Established joint venture, Denyo Manufacturing Corporation in U.S.A. |
| December 1997 |
Received ISO 9001 certification for Fukui plant |
| March 2000 |
Listed on the First Section of the Tokyo Stock Exchange |
| June 2000 |
Established Singapore subsidiary, Denyo Asia Pte. Ltd. |
| December 2006 |
Denyo moved to Nihonbashi-horidomecho |
| June 2007 |
Acquisition of Nishinihon Generator Mfg. Co., Ltd. (currently Nishihatsu Co., Ltd. ) as subsidiary |
| October 2007 |
Established subsidiary, Denyo Europe B.V. in the Netherlands |
| July 2009 |
Absorption-type merger of Denyo techno Service Co., Ltd. and Denyo Trading Co., Ltd. |
| May 2010 |
Established subsidiary, Denyo Vietnam Co., Ltd. |
| March 2013 |
Established Laboratory & Training Center in Sakado city, Saitama |
| February 2015 |
Began to manufacture engine-driven generators, with the completion of the second factory in Denyo Vietnam Co., Ltd. |
| February 2020 |
Established subsidiary, Denyo Trading Vietnam Co., Ltd. |
| April 2022 |
Transited to Prime Market in Tokyo Stock Exchange |
| March 2023 |
Established Service Center Kanto in Sakura city, Chiba |
| January 2025 |
Nishihatsu Co.,Ltd. commenced operations at the new headquarters factory. |
| April 2025 |
Established Service Center West Japan in Okayama city, Okayama |
