An apparatus detects a predetermined number of facial images from detection target images. An inclination order setting means utilizes the correlative relationships among correlative data obtained by a correlative data obtaining means and the inclinations of faces that appear in input images, to determine the relative value of the probability that faces of a predetermined inclination will appear in the input images. The inclination order setting means sets the order of inclinations of faces to be detected such that faces are detected in order of inclinations according to the relative values of the probabilities, based on the correlative data that they will appear. A face detecting means detects faces within the input images while varying the inclinations of faces to be detected according to the set order.