PROBLEM TO BE SOLVED: To provide a disposable diaper capable of effectively supporting the understanding of a general worker with respect to the casting of upper and lower fastening parts and a putting way at the time of putting of the diaper.SOLUTION: The disposable diaper 10 includes a diaper body 11, the upper and lower fastening parts 41 and 42 each having adhesion elements 32 and provided in the longitudinal direction Y of the diaper body 11 on both sides of the lateral direction X in the parts on the rear side of the longitudinal direction Y of the diaper body 11 so as to leave a gap and the adhesion sheet 13 which is provided on the outer surface side in the part on the front side of the diaper body 11 and to which the adhesion elements 32 of the upper and lower fastening parts 41 and 42 are adhered in a freely detachable manner. The upper and lower fastening parts 41 and 42 are mutually different at least in either one of a color, a pattern, a shape and a size.