An electronic key actively executes wireless communication following a keyless entry communication and passively executes wireless communication following a RFID communication. A vehicle control device is mounted on a vehicle and actively executes wireless communication following each of the keyless entry communication and RFID communication. An ECU/BCM unlocks a door by communicating with the electronic key using the keyless entry communication and issues a password to the electronic key in relation to this action. When a door knob or handle is pulled, an RFID-IC acquires the password issued by the ECU/BCM from the electronic key using the RFID communication and unlocks the door by authenticating the acquired password.