A fuser allows a sheet medium on which a toner image has formed to path through while heating the sheet medium, thereby fusing the toner image on the sheet medium. A plurality of first rollers are arrayed in a first direction. A plurality of second rollers are arrayed in the first direction and respectively coming in contact with the first rollers with a first pressure. The second rollers are adapted to eject the sheet medium nipped between the first rollers and the second rollers to the outside of the apparatus in a second direction perpendicular to the first direction. A plurality of third rollers are arrayed in the first direction so that each of the third rollers is disposed between adjacent ones of the first rollers, the third roller adapted to be brought into contact with the sheet medium with a second pressure which is smaller than the first pressure.