A disposable pant-shaped diaper (1) which comprises an absorbent body (10) and an outer sheet (20) provided in the outer face side of this absorbent body (10) and in which the front corsage and the back corsage of the outer sheet (20) are bonded together at both sides, wherein the outer sheet (20) has elastic and stretch waist members located around the waist opening and a plural number of elastic and stretch hipline members horizontally located in the front corsage (F) and the back corsage (B) at intervals in the up and down direction, at the both sides where the front corsage and the back corsage are bonded together, side flaps (32,32) extending outward from the bonding parts are provided, and a fastening device (33) mechanically engageable with the outer face of the front corsage is provided in the front face side of each side flap (32).
