A game program KGP for playing a game by operating a keyboard connected with a computer in response to a picture displayed on a monitor 9 has a procedure for detecting and computing number of keys (S2 through S9), for detecting and computing number of keys of the keyboard 17 connected with a game machine body, and a procedure for setting key set (S9 through S13), for setting one or more key sets on the keyboard according to the number of keys if the detected number of keys is a predetermined number of keys or more. Then, people can easily enjoy the keyboard game program with only a general purpose keyboard, and it is not necessary to specifically prepare a dedicated controller, thereby providing the game program usable for various purposes.