PURPOSE: To maintain the latest data as menu data in the data input system which employs menu selecting operation.

CONSTITUTION: At a menu display request inputted through the request input means 305 of a terminal device 300, a menu data retrieving means 204 is actuated through the request receiving means 206 of a host computer 200. The menu data retrieving means 204 retrieves menu data in a data base 201 and the retrieved data are outputted to a menu data receiving means 304 through a menu data transmitting means 205 and a communication means 100 to display a menu by a menu display means 303. The menu selected by a menu selective input means 302 is transmitted to a data writing means 202 similarly through a data transmitting means 301 and the communication means 100 and written in the data base 201.