A diaper includes front and rear waist panels respectively defining front and rear waist regions, a crotch panel defining a crotch region, and an absorbent structure extending in a longitudinal direction. The crotch panel has a base sheet and a pair of leg sheets attached to both lateral edge portions of the base sheet. In vicinities of front and rear end portions of the crotch panel, first joint regions extending in a transverse direction from the base sheet beyond outer lateral edge portions of the respective leg sheets are formed. Through these joint regions, the crotch panel is joined to the front and rear waist panels. Cover sheets adapted to cover the front and rear end portions are joined to an interior crotch sheet of the crotch panel through second joint regions. The cover sheets extend outwardly in the transverse direction beyond the first joint regions.