The present invention is intended to make the deformation of the absorber at the crotch portion less prone to influence the waist side of the absorber and allow the waist side of the absorber to be easily rounded along the surface of the wearer's body. The foregoing issue is solved by a disposable diaper including an absorber (13) in a crotch portion, a ventral-side portion, and a dorsal-side portion, wherein the absorber (13) is divided in a front-back direction by width-direction slits (13S) continuing in the width direction provided on both front and back sides of the crotch portion, and concave portions (17u) (19u) recessed toward the waist side are formed in width-direction centers of waist-side edges of the width-direction slits (13S).
