Provided is a vehicle periphery monitor device for accurately distinguishing between and detecting two side-by-side pedestrians and a vehicle that is lighting lights. With regard to a pedestrian candidate having at least two head candidates, a reference image creation unit creates the peripheral image of one of the head candidates as a reference image and creates an inverted image in which the right and left sides of the reference image are inverted. An object determination unit sets the peripheral image of the other heat candidate as a comparative image, and determines whether the head candidates are the pedestrians or the vehicle on the basis of the consistency of the reference image and the inverted image relative to the comparative image.