A pedestrian collision detecting apparatus for motor vehicles is provided which works to distinguish between impacts with pedestrians and other sorts of impacts using a combination of a collision duration for which a sensor continues to sense a physical impact arising from collision with an object and a time-sequential change in locations of collisions of the vehicle with objects, thereby ensuring the reliability of detection of a pedestrian-vehicle collision and allowing the size and production costs of the apparatus to be minimized to improve the mountability of the apparatus in motor vehicles.