A fixing device that fixes an elastic sheet (8a) that is transported along a transport direction and a low-stretchable sheet (9a) that has lower stretchability than that of the elastic sheet via a plurality of fixing parts (j) while superposing the elastic sheet and the low-stretchable sheet in a thickness direction. The fixing device includes: a rotating member (15a) that includes a plurality of protrusions (15at) on an outer peripheral surface to form the plurality of fixing parts and rotates along the transport direction and a sandwiching member (15h) that is arranged at a predetermined position of the rotating member in a rotational direction, and sandwiches the elastic sheet and the low-stretchable sheet by a surface portion (15hs) in cooperation with each of the protrusions to form the fixing parts when each of the protrusions passes through the predetermined position, the surface portion being larger than a top surface of each of the protrusions. At a sandwiching position in which the elastic sheet and the low-stretchable sheet are sandwiched cooperatively by the sandwiching member and the rotating member, the low-stretchable sheet is located between the elastic sheet and the top surface of each of the protrusions of the rotating member.
