To accurately judge whether own-car can pass through a curve in front of the traveling direction or not.

A temporary own-car position setting means M4 sets a temporary own-car position in front of the own-car position, and an estimated passing speed computing means M5 computes the estimated passing speed on the basis of a distance between the own-car position and the temporary own-car position. A curvature and radius computing means M6 and a curve length computing means M7 compute the curvature, radius and length of a curve, which exists in a road in front of the temporary own-car position, on the basis of the map information output from a map information output means M1. A passing property judging means M9 compares the estimated passing speed with the appropriate passing speed so as to judge whether the own-car can pass through a curve or not, and in the case where a judgment that the own-car can not pass through the curve is performed, a vehicle control means M10 controls the vehicle so that it can pass through the curve.