Mobile object communication system and mobile object side device

A mobile object communication system includes a mobile object side device, a service provision device performing a short range wireless communication with the mobile object side device to provide a service to the mobile object side device, and a wide area route provision unit performing a wide area communication with the mobile object side device to provide the service having the same contents as the service provided by the service provision device. The mobile object side device can perform both of the short range wireless communication and the wide area communication, and determines whether the short range wireless communication can be performed with the service provision device. When determining that the short range wireless communication cannot be performed, the service having the same contents is provided by performing the wide area communication with the wide area route provision unit.