| 1907 | Founded by the late Kyutarou Ito, Ito Iron Works |
| 1946 | Designed and manufactured alloy casting tools and related equipment for Buddhist implements |
| 1956 | Started designing and manufacturing diatomite moisture brick production plants |
| 1956 | Succession to Eikichi Ito |
| 1959 | Started manufacturing pressure fittings for piping |
| 1962 | Started manufacturing Mitsubishi Heavy Industries' Eco-Rite 1000 intake manifolds |
| 1966 | Moved to the current Kuze Industrial Complex |
| 1968 | Started designing and manufacturing molds for fine ceramics |
| 1969 | Reorganized into Ito Seiko Co., Ltd. |
| 1971 | Started manufacturing Ito-style ground flow boilers |
| 1975 | Started designing and manufacturing molds for TAB films |
| 1988 | Developed molds with EDM slit blades |
| 1992 | Completed new company building at the current location |
| 1995 | Significantly expanded pin manufacturing department |
| 2001 | Started focusing on micro machining; began exhibiting at the Micromachine Exhibition |
| 2002 | Obtained ISO9001 certification for design and manufacturing |
| 2003 | Entered the nanotech and medical fields |
| 2005 | Entered the glass processing field |
| 2007 | Kohei Hasegawa appointed as President and CEO; Akemi Ito appointed as Vice President |
| 2017 | Introduced high precision pico second laser |
| 2023 | Introduced femto second laser for micro machining |
