This underpants-type absorbent article is provided with: an absorbent body (10)； a back-side waistline part (20) positioned on one end side of the absorbent body (10)； an abdomen-side waistline part (30) positioned on the other end side of the absorbent body (10)； and a pair of joint regions (40) in which both end portions of the abdomen-side waistline part (30) in the horizontal direction are joined with both end portions of the back-waistline part (20) in the horizontal direction. The upper end portion of the back-side waistline part (20) in the vertical direction is positioned above the upper end portion of the abdomen-side waistline part (30) in the vertical direction, and high-density regions (50) having higher densities than those of the surroundings are provided in both end portions in the horizontal direction in the upper end portion of the back-side waistline part (20).
