The present invention aims to provide a disposable diaper improved so that the wearers skin can be reliably protected from being soiled with feces. A chassis (11) constituting the diaper (1) includes a spacer sheet (17) attached to an inner sheet (11a) of the chassis (11). The spacer sheet (17) has a front end zone (17a) and a rear end zone (17b) fixed to the inner sheet (11a) and an intermediate zone (17d) left free from the inner sheet (11a). The intermediate zone (17d) is formed with an opening (26) shaped so as to describe a circular arc which is convex forward. Along the opposite side edges of the opening (26), the spacer sheet (17) is provided with elastic members (27) extending in the length direction (L) of the diaper (1) and attached thereto in a stretched state in the direction (L). These elastic members (27) extend forward with respect to the diaper (1) along the peripheral edge of the opening so as to get close to a center line (C) bisecting a width of the diaper (1).
