A leak-proof cuff (28) is divided into a lower region (40) and a upper region (41). The upper region (41) includes a first region (41A) located at the side of a free edge (28B) relative to the center in the width direction (Y) and a second region (41B) located at the side of a folding line (42). In each of the first region (41A) and the second region (41B), at least one elastic member (29) extending along the longitudinal direction (X) is provided in a stretched state. In a case where the elongation of the upper region (41) in a natural state is 0, and the elongation in a maximum stretched state is 100, the stress σ1 of the first region (41A) is larger than the stress σ2 of the second region (41B) at an elongation of 5, and the stress σ2 of the second region (41B) is larger than the stress σ1 of the first region (41A) at an elongation of 100.