An absorbent article includes: an absorbent body (11) having a longitudinal direction and a lateral direction orthogonal to each other； and a pair of leak-proof walls (50) provided on both lateral sides of the absorbent body (11). Each of the leak-proof walls is formed of a sheet member (50s) including a plurality of first welded parts (61) on a surface of the sheet member (50s). And, each of the leak-proof walls (50) includes an overlaid part (50L) where the sheet member (50s) is overlaid in a thickness direction such that an elastic member (52) stretching/contracting in the longitudinal direction is sandwiched. In at least a part of a region of the overlaid part (50L), a plurality of second welded parts (62) that join the overlaid sheet member (50s) is disposed. An area of the second welded parts (62) is smaller than an area of the first welded parts (61).
