An image processing apparatus includes a detecting unit for detecting a position of a facial feature in a face image, a principal component analysis performing unit for performing principal component analysis on the position of the facial feature in a registered image that is a pre-registered face image, a first evaluation value calculating unit for calculating a first evaluation value that is used to evaluate the position of the facial feature in a target image relative to the principal component obtained in the principal component analysis operation, and a first determining unit for determining whether or not the face in the target image matches the face in the registered image by comparing the calculated first evaluation value with a first threshold set based on the position of the facial feature in the registered image relative to the principal component.