An information storage device, by which only information outputted in a state desired by a user can be stored and disclosed with minimum time and trouble of the user, is provided. After FAX transmission, the FAX image is displayed and an inquiry concerning whether to store the FAX image or not is conducted. When the user performs an operation designating registration of the FAX image in a database (i.e. when a registration command button is pressed by the user), the FAX image is registered in the database. When the user performs an operation designating discard of the FAX image (i.e. when a discard command button is pressed by the user), the FAX image is discarded. Since the user can decide whether or not to register the FAX image in the database after checking the image to be registered, registration of undesired image in the database can be prevented.