A pull-on absorbent article 1 including a front outer cover 2A to be worn around a wearer's front side, a rear outer cover 2B to be worn around the wearer's rear side, and an absorbent assembly 3 fixed to the front and the rear outer cover so as to bridge them and having a pair of side seals 4 and 4. The length of each of the front and the outer cover 2A and 2B in the longitudinal direction of the article is uniform in the lateral direction and larger than that of the side seals 4 so that the front and the outer cover have extension portions 21a and 21b, respectively, that extend downward from the side seals. The extension portion 21a and/or the extension portion 21b of the front and/or the rear outer cover has/have an elasticized region extensible in the lateral direction in a region located laterally outward of each side edge of the absorbent assembly 3.
