A pull-on absorbent article having a vertical direction and a lateral direction, the pull-on absorbent article comprising: an absorbent main body including an absorbent body , the absorbent main body having a longitudinal direction that conforms to the vertical direction; and waist-circumference sections in a pair respectively located on one end side and another end side in the longitudinal direction of the absorbent main body , the waist-circumference sections including an elastic member stretchable in the lateral direction, the absorbent main body including extension sections in a pair respectively extending outward on two lateral sides of the absorbent body , the extension sections each having an elastic member stretchable in the vertical direction placed therein, the extension sections each forming a leg opening and including an overlap portion that overlaps in the vertical direction with at least one of the waist-circumference sections in a pair, the extension section and the waist-circumference section being joined together in at least a part of the overlap portion , the overlap portion , in the extension section , having a welded region placed therein, the welded region having a predetermined length (L1) in the lateral direction and being elongated in the lateral direction, wherein a plurality of the elastic members stretchable in the lateral direction are placed at an interval (L3) in the vertical direction in the waist-circumference section , a plurality of the welded regions are placed at an interval (L2) in the vertical direction in the overlap portion of each of the extension sections , and the interval (L3) in the vertical direction between the plurality of elastic members placed in the waist-circumference section is smaller than the interval (L2) in the vertical direction between the plurality of welded regions . an absorbent main body including an absorbent body , the absorbent main body having a longitudinal direction that conforms to the vertical direction; and waist-circumference sections in a pair respectively located on one end side and another end side in the longitudinal direction of the absorbent main body , the waist-circumference sections including an elastic member stretchable in the lateral direction, the absorbent main body including extension sections in a pair respectively extending outward on two lateral sides of the absorbent body , the extension sections each having an elastic member stretchable in the vertical direction placed therein, the extension sections each forming a leg opening and including an overlap portion that overlaps in the vertical direction with at least one of the waist-circumference sections in a pair, the extension section and the waist-circumference section being joined together in at least a part of the overlap portion , the overlap portion , in the extension section , having a welded region placed therein, the welded region having a predetermined length (L1) in the lateral direction and being elongated in the lateral direction, wherein a plurality of the elastic members stretchable in the lateral direction are placed at an interval (L3) in the vertical direction in the waist-circumference section , a plurality of the welded regions are placed at an interval (L2) in the vertical direction in the overlap portion of each of the extension sections , and the interval (L3) in the vertical direction between the plurality of elastic members placed in the waist-circumference section is smaller than the interval (L2) in the vertical direction between the plurality of welded regions . <EOS>