An underpants-type absorbent article (1) configured with an absorbent article having an abdomen side part (11a) that is to be arranged on an abdomen side of a wearer, a back side part (11b) that is to be arranged on a back side of the wearer and a crotch part (11c) that is to be arranged to a crotch of the wearer when worn, the absorbent article being welded at respective horizontally outward end parts (11es) of the abdomen side part (12a) and the back side part (12b) when the absorbent article is in a state folded into two at the crotch part (12c) with the abdomen side part overlapping the back side part to form a body encircling opening (1HB) and a pair of leg encircling openings (1HL) at mutually different locations along a vertical direction that intersects the horizontal direction, the underpants-type absorbent article including a plurality of welded parts (j, j1, j2, j3, j4, j5, j6, j7, j8) that are formed at the end part in a non-continuous welding pattern along at least the vertical direction； and an inner area and an outer area (Ain, Aout) that are included in the end part, the inner area being located horizontally inward and the outer area being located horizontally outward with respect to the inner area； wherein the welded parts are formed to a predetermined range along the vertical direction, the predetermined range starting from the body encircling opening of the end part, such that a vertical dimension of a space between vertically adjacent welded parts in the inner area is made larger than the vertical dimension of a space between the vertically adjacent welded parts in the outer area, and the welded parts each has on the body encircling opening side a slanted shape portion (jlu, j2u, j3u, j4u), the slanting portion slanting toward the leg encircling 5 opening in the vertical direction as approaching to an outside along the horizontal direction, the welded parts being formed in pluralities and arranged along the vertical direction at the inner area in
