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 (20, 30) 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 (20, 30) including an elastic member (22, 32) 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 (20, 30)in a pair, the extension section and the waist-circumference section (20, 30) 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 in the lateral direction and being elongated in the lateral direction, wherein a plurality of the elastic members (22, 32) stretchable in the lateral direction are placed at an interval in the vertical direction in the waist-circumference section (20, 30), a plurality of the welded regions are placed at an interval in the vertical direction in the overlap portion of each of the extension sections, and the interval in the vertical direction between the plurality of elastic members (22, 32) placed in the waist-circumference section (20, 30) is smaller than the interval 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 (20, 30) 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 (20, 30) including an elastic member (22, 32) 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 (20, 30)in a pair, the extension section and the waist-circumference section (20, 30) 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 in the lateral direction and being elongated in the lateral direction, wherein a plurality of the elastic members (22, 32) stretchable in the lateral direction are placed at an interval in the vertical direction in the waist-circumference section (20, 30), a plurality of the welded regions are placed at an interval in the vertical direction in the overlap portion of each of the extension sections, and the interval in the vertical direction between the plurality of elastic members (22, 32) placed in the waist-circumference section (20, 30) is smaller than the interval in the vertical direction between the plurality of welded regions.