A disposable diaper 1 includes a side flap 30 and a tape fastener 40. The tape fastener 40 includes a tape attaching part 41 attached to the side flap 30 and exposed at an outer side face of the side flap. The side flap 30 includes a leg periphery side region 301 positioned closer to a leg of a wearer than the tape attaching part 41. The leg periphery side region 301 is foldable upwardly to cover at least partially an end portion of the tape attaching part 41 adjacent the leg of the wearer in response to a stress generated when the tape fastener 40 is engaged, while being pulled, with the other end portion of the inner part in the longitudinal direction.
