Casio traces its origins to Kashio Seisakujo, founded by Tadao Kashio in Mitaka, Tokyo, Japan in 1946, while Casio Computer Co., Ltd. was established in 1957.

Casio entered the watch business in November 1974 with the CASIOTRON digital watch, featuring an automatic calendar that accounted for different month lengths. Its shock-resistant G-SHOCK range was launched in 1983. Other collections include PRO TREK outdoor watches and EDIFICE metal chronographs.