1. A vehicle surroundings monitoring apparatus comprising: an object extraction process unit which extracts an object existing in an imaging area of a camera mounted on a vehicle from an image captured by the camera; an object type determination process unit which determines the type of the extracted object on the basis of the image of the object in the captured image; and a vertical symmetry determination process unit which determines whether the degree of vertical symmetry of the extracted object is high or low on the basis of the image of the object in the captured image, wherein the object type determination process unit includes at least a first-type determination process unit which determines the type of the extracted object on the basis of the determination result of the vertical symmetry determination process unit.