A disposable diaper provided with elastic stretchable members which cause a separation sheet to be in close contact with the wearers body and can maintain openings in a desired shape. A separation sheet (14) is provided with: a front section (30) which is provided in a crotch region (13) of a diaper body (10a) and which is located near a front waist region (11) a rear section (31) which is located near a rear waist region (12) and an intermediate section (32) which is located between the front section (30) and the rear section (31). Openings (34, 35) are a front opening (34) which is defined in the front section (30) and a rear opening (35) which is defined in the rear section (31). A pair of front elastic stretchable members (38, 39) extends in a contractible manner from both sides of a front end section (14a) of the separation sheet (14) to the rear peripheral edge of the front opening (34) so as to be symmetric about a vertical axis (P), a pair of rear elastic stretchable members (40, 41) extends in a contractible manner from both sides of a rear end section (14b) of the separation sheet (14) to the front peripheral edge of the rear opening (35) so as to be symmetric about the vertical axis (P), and the front opening (34) and the rear opening (35) are arranged in such a manner that, when the intermediate section (32) of the separation sheet (14) is folded, the front opening (34) and the rear opening (35) are located adjacent, near a lateral axis (Q), to each other in the direction of the vertical axis (P). The pair of front elastic stretchable members (38, 39) and the pair of rear elastic stretchable members (40, 41) face each other and are separated from each other in the intermediate section (32).
