Authentication and registration system

An authentication and registration system is provided which can reduce a burden at the time of authentication and registration while ensuring security when a single apparatus is used to perform authentication and registration of identification information on another apparatus. In an authentication and registration system (1), an authentication request signal is transmitted from a mobile terminal (3) to a registration server (2). The registration server (2) transmits an operation command signal to the mobile terminal (3) and when the signal is received, a display (3b) of the mobile terminal (3) displays operation sub-commands. When the sub-commands are executed through operations of switches (10) to (20), an on-board controller (4) transmits an operating state signal indicating the execution to the registration server (2). When the operating state signal indicates that the sub-commands are executed, the registration server (2) determines that authentication of the identification information succeeds.