To provide a relative position identification device capable of compensating inaccuracy of a satellite positioning without adding any special auxiliary information device.

A relative position identification device comprises: inter-vehicle communication equipment 2 which acquires positional information positioned by another vehicle by communication with the other vehicle; a positioning derivation azimuth identification part 3 which identifies the azimuth of the other vehicle to a self-vehicle by the positional information positioned of the self-vehicle and the positional information positioned of the other vehicle; and radio wave azimuth detection means 4 which detects the incoming azimuth of a communication radio wave from the other vehicle; and a radio wave derivation azimuth identification part 5 which identifies the azimuth of the other vehicle to the self-vehicle based on the incoming azimuth of the communication radio wave from the other vehicle.