PROBLEM TO BE SOLVED: To provide an underpants type absorbent article which has an appearance like underwear while having a side seal part, has excellent perceptibility from the outside in the side seal part, and can be easily torn.SOLUTION: A side seal part 4 of an underpants type absorbent article 1 has a first region 4A in which a length in a width direction is relatively short and a length in a longitudinal direction is relatively long, and a second region 4B in which a length in the width direction is relatively longer than that of the first region 4A and a length in the longitudinal direction is relatively shorter. A part of a plurality of elastic members 5 provided in an exterior body 3 is arranged in such a manner that an end part is positioned in the first region 4A. As a result, contracting force of the elastic member 5 generated in expanding the exterior body 3 in the width direction acts on the first region 4A, and the first region 4A is bent to the inside in the width direction while the article 1 is worn.
