PROBLEM TO BE SOLVED: To provide a underwear-type absorbent article capable of forming a disposal configuration that allows excrement in a diaper to be surely stored through a simple operation.SOLUTION: A diaper 1 is an underwear-type diaper that has an abdominal side part A, a back side part B and a crotch part C, and includes an outer body 2 and an absorbent body 3 located inside the outer body 2 and including an absorber 31 and a cover member 33. The absorber 31 has a back side cut part 313 cut in a projecting shape and having a cover member 6, at its end 311b on the side of the back side part B. A fastening tape 8 is disposed between both ends at the back waist open side of the back side cut part 313 on the outer surface of the back side part B of the outer body 2. In its thickness direction, the fastening tape 8 is disposed in such a manner as to not overlap with the absorber 31 but with the cover member 6.
