The front part and the rear part of a diaper main body (2) are each attracted by a first belt (20) and a second belt (27) arranged so as to face each other across a conveying path (R1) and separate from each other as the first belt (20) and the second belt (27) move to the downstream side of the conveying path (R). Here, the diaper main body (2) is attracted by the first belt (20) only in a range other than a non-attracting range (E1) thereof covering from a crease (2A) to a prescribed position in a longitudinal direction. When the respective belts (20 and 27) are moved in this state, the front part and the rear part of the diaper main body (2) are separated from each other in a state in which the diaper main body (2) separates from the first belt (20) in the non-attracting range (E1) while the disposable diaper (1) is conveyed such that the crease (2A) is directed to the downstream side. Then, respective side panels (3 and 4) are folded inward between the front part and the rear part of the diaper main body (2) that separate from each other.
