To disuse an engine key and improve security compared with a conventional device by providing a function of an immobilizer in an on-vehicle unit for dedicated short range communication.

The on-vehicle device includes a transmitting and receiving part mounted on a vehicle for transmitting and receiving data with an on-road unit through an antenna, an IC card interface part connected to an external IC card, a non-volatile memory for storing reference information, a security module part for collating information obtained from the IC card and the reference information, and a controlling part for controlling the transmitting and receiving part, the IC card interface part, and the security module part, and performs a charging process with the on-road unit on the basis of the information obtained from the IC card. The controlling part outputs a signal for external control on the basis of output of the security module part.