A disposable diaper (10) comprises a sheet-shaped elastic element (100) which is disposed in a rear torso surrounding region (30). The sheet-shaped elastic element (100) further comprises a stretching region (105) which is stretchable in the product width direction (W). An absorbent body (40) comprises: a low-rigidity region (110) with a lower basis weight than other sites of the absorbent body (40), or where the absorbent core is absent; and a non-stretching region (45) which does not stretch in the product width direction (W). The non-stretching region (45) is disposed closer to the inseam region than the stretching region (105). The stretching region (105) overlaps with at least a portion of the low-rigidity region (110) in the plan view of the disposable diaper (10). The width of the low-rigidity region (110) in the product width direction (W) increases toward end parts of the rear torso surrounding region (30) in the product longitudinal direction (L).