A disposable diaper has a through-hole formed in an inner sheet destined to come in contact with a wearer's skin so that this through-hole may communicate with a pocket for receiving feces. The inner sheet is formed with an elastic area extending in a longitudinal direction along transversely opposite side edges of the through-hole. In a crotch region of the diaper, a stiffening sheet strips are attached to the inner sheet between the transversely opposite side edges of the diaper and the transversely opposite side edges so that the respective stiffening sheet strips extend in a transverse direction.