This disposable diaper (1) has abdominal waist flaps (FA) and back waist flaps (FB) located to the outside of the front and back ends (23A, 23B) in the longitudinal direction (X) of an absorbent (23) and extending in the transverse direction (Y). The back waist flaps (FB) have a hydrophobic skin-side sheet (4) and a hydrophilic non-skin-side sheet (5). The skin-side sheet (4) is provided with depressions (41) that form hollows toward the non-skin-side sheet (5) and openings (44) in the depressions (41) that pass through to the skin-side sheet (4). The thickness of the depressions (41) of the skin-side sheet (4) is smaller closer to the openings (44).
