A pull-on absorbent article including a front outer cover to be worn around a wearer's front side, a rear outer cover to be worn around the wearer's rear side, and an absorbent assembly fixed to the front and the rear outer cover so as to bridge them and having a pair of side seals. The length of each of the front and the outer cover in the longitudinal direction of the article is uniform in the lateral direction and larger than that of the side seals so that the front and the outer cover have extension portions that extend downward from the side seals. The extension portions of the front and/or the rear outer cover have an elasticized region extensible in the lateral direction in a region located laterally outward of each side edge of the absorbent assembly.
