An absorber 40 of a disposable diaper 10 includes a first region 41 at least partially arranged in the crotch stretch unit 200a and a second region 42 arranged adjacent to the first region at an outer side from the first region in the product longitudinal direction and having a lower bending rigidity than that of the first region. A boundary between the first region and the second region is arranged at an outer side from an outer end of the crotch stretch unit in the product longitudinal direction and is arranged at an inner side from an outer end of the leg stretch unit in the product longitudinal direction.