Provided is disposable underwear that fits well to the body and inhibits the underwear from slipping down. A pant-type diaper (1) is characterized by being provided with: a ventral member (11) a dorsal member (12) a crotch member (5) that connects both members left and right leg openings (13, 14) that are formed by bonding the left ends (15a, 15b) and the right ends (15c, 15d) of the ventral member (11) and the dorsal member (12), thereby enclosing the left and right leg openings (13, 14) by the ventral member (11), the dorsal member (12) and the crotch member (5) and waist-surrounding elastic bodies (21, 21a, 21b) that extend leftwards and rightwards from the ventral member (11) and the dorsal member (12), and that are disposed in a region below lumbar parts (4, 4a, 4b) along the upper edges of both members (11, 12) and above the left and right leg openings (13, 14). The pant-type diaper (1) is further characterized by the tightening force of at least some of the waist-surrounding elastic bodies (21, 21a, 21b) gradually weakening from the lumbar parts (4, 4a, 4b) towards the left and right leg openings (13, 14).Linvention concerne un sous-vêtement jetable, lequel sadapte facilement au corps dun utilisateur, et lequel permet de supprimer les glissements vers le bas. Plus spécifiquement, une couche (1) de type culotte comporte: un élément (11) côté ventre un élément (12) côté dos un élément fourche (5) qui relie les deux éléments précédents des parties ouvertures (13, 14) pour les jambes, formées par assemblage entre elles de parties dextrémité (15a, 15b) gauches et de parties dextrémité (15c, 15d) droites de lélément (11) côté ventre et de lélément (12) côté dos, de façon à être entourées par lélément (11) côté ventre, lélément (12) côté dos et lélément fourche (5) des corps élastiques (21, 21a, 21b) entourant le tronc, lesquels sétendent vers la droite et vers la gauche de lélément (11) côté ventre et de lélément (12) côté dos, et lesquels sont positionnés dans une
