An underpants-type disposable diaper, including: an outer body constituting a front panel and a back panel, and an inner body that includes an absorber and is fixed to the inner surface of the outer body, wherein the front panel of the outer body and the back panel of the outer body are joined together at the both sides to form side seal portions, thereby forming an annular waist portion and a waist opening and a pair of right and left leg openings, a waist edge portion of the outer body includes a plurality of elongated waist edge portion resilient and elastic members provided along a width direction and separated from each other, an inner layer composed of a sheet material facing the inside of the waist edge portion resilient and elastic members, and an outer layer composed of a sheet material facing the outside of the waist edge portion resilient and elastic members, the inner layer and the outer layer are joined by an adhesive arranged intermittently or a welding process performed intermittently in the width direction and continuously in a direction crossing the width direction, thereby forming sheet joined sections, the waist edge portion resilient and elastic members are fixed to at least one of the inner layer and the outer layer at positions intersecting with the sheet joined sections, the inner layer and the outer layer contracting as the waist edge portion resilient and elastic members contract, portions positioned between the sheet joined sections in the inner layer and the outer layer swell inversely to each other, thus respectively forming pleats, and the diaper includes an area not being joined and not having resilient and elastic member at an end portion of the outer body on the waist opening side in the waist edge portion, the area not having sheet joined sections nor the waist edge portion resilient and elastic members, and a vertical range being wider than spacing between the waist edge portion resilient and elastic member positioned closest to the waist opening side, and the waist edge portion resilient and elastic member adjacent thereto, wherein there is no hard sheet joined sections at the end portion on the side of the waist opening. an outer body constituting a front panel and a back panel, and an inner body that includes an absorber and is fixed to the inner surface of the outer body, wherein the front panel of the outer body and the back panel of the outer body are joined together at the both sides to form side seal portions, thereby forming an annular waist portion and a waist opening and a pair of right and left leg openings, a waist edge portion of the outer body includes a plurality of elongated waist edge portion resilient and elastic members provided along a width direction and separated from each other, an inner layer composed of a sheet material facing the inside of the waist edge portion resilient and elastic members, and an outer layer composed of a sheet material facing the outside of the waist edge portion resilient and elastic members, the inner layer and the outer layer are joined by an adhesive arranged intermittently or a welding process performed intermittently in the width direction and continuously in a direction crossing the width direction, thereby forming sheet joined sections, the waist edge portion resilient and elastic members are fixed to at least one of the inner layer and the outer layer at positions intersecting with the sheet joined sections, the inner layer and the outer layer contracting as the waist edge portion resilient and elastic members contract, portions positioned between the sheet joined sections in the inner layer and the outer layer swell inversely to each other, thus respectively forming pleats, and the diaper includes an area not being joined and not having resilient and elastic member at an end portion of the outer body on the waist opening side in the waist edge portion, the area not having sheet joined sections nor the waist edge portion resilient and elastic members, and a vertical range being wider than spacing between the waist edge portion resilient and elastic member positioned closest to the waist opening side, and the waist edge portion resilient and elastic member adjacent thereto, wherein there is no hard sheet joined sections at the end portion on the side of the waist opening.