To accurately display an own vehicle position on a road map at a high speed.

In the case that an own vehicle enters an area in which information provision is received from a road side antenna and a prescribed period does not elapse after it enter the area (YES in S1 and No in S2), road data corresponding to an information provision road is preferentially selected even when a traveling track is similar to the road data corresponding to a non- information provision road of the road data in a map data memory related to an own vehicle position data, and the own vehicle position data is matched to the road data (S3).