A disposable pant-type diaper according to the present invention includes a front portion, a back portion, and a crotch portion which is positioned between the front and back portions, in which a waist opening and a pair of leg openings are formed by joining both longitudinal side-edge portions of the front and back portions which face each other, and stretchable elastic members are disposed along at least a part of each opening, wherein a cutout portion is formed in at least a portion of the side-edge portion of at least one of the front and back portions, and the front and back portions assume a non-joining state at the portion where the cutout portion is formed.
