A finger/palm-print image processing apparatus comprises: an image converting means that converts finger/palm-print images to conversion images consisting of first and second sets of elements; and an area detecting means that detects, from the conversion images as converted by the image converting means, an area where the number of the first set of elements is equal to or greater than a predetermined number. The first and second sets of elements herein are the elements of sets each of which consists of elements of the finger/palm-print images. The first set of elements have those degrees of change in color information which meet a predetermined criterion, while the second set of elements have those degrees of change in color information which do not meet the predetermined criterion.