[Problem] To provide an underpants-type disposable diaper in which a part where the underpants-type disposable diaper does not overlap with an absorbing element is thin and suitable for expansion and contraction, whereas a part where the underpants-type disposable diaper overlaps with the absorbing element has an excellent fluffy feeling to the touch. [Solution] The present invention that solves the above described problem is provided with a front side exterior body (12F), a rear side exterior body (12B), and an interior body (200) that is attached so as to reach from the front side exterior body (12F) to the rear side exterior body (12B) and incorporates an absorbing element (50), wherein: a cover sheet (13) that comprises a non-woven fabric and extends in a front-rear direction (LD) outside an outer sheet layer (12S) in an exterior body at the center side in a width direction with respect to the positions of both side rims of the absorbing element (50) is provided no non-woven fabric other than the cover sheet (13) is provided, outside the positions of both side rims of the absorbing element (50) in a width direction and outside the outer sheet layer (12S) in the exterior body and at least both side end portions of the inner surface of the cover sheet (13) are adhered, via a hot melt adhesive (13H), to their respective opposing surfaces in an area excluding front and rear end portions.
