Abstract: A remote control system comprises a machine tool controller and an operation terminal apparatus remotely located from the machine tool and connected via a network to the machine tool controller. The operation terminal apparatus comprises a registered name input section and an authorization level database that matches a registered name to an authorization level, and the operation terminal transmits the authorization level corresponding to the registered name to the machine tool controller. The machine tool controller comprises a restricted function database that matches an authorization level to operation-allowed or operation-forbidden function, and the machine tool controller specifies the operation-allowed or operation-forbidden function corresponding to the authorization level, and restricts function of the machine tool controller.