A duct for an image forming apparatus for forming an image on a recording material, the duct includes a discharge opening for discharging air; a fan, mounted to a neighborhood of the discharge opening, for discharging the air; first and second openings for suction of air; a first guiding portion, having first and second openings, for guiding the sucked air; a separation member, provided in the first guiding portion, for separating a flow of the air sucked by the first opening and a flow of the air sucked by the second opening; a second guiding member, disposed overlapped with the first guiding portion, for guiding the air guided by the first guiding portion; a first interconnection opening for feeding the air from the first opening to the second guiding portion; a second interconnection opening for feeding the air from the second opening to the second guiding portion, wherein the first interconnection opening is disposed closer to the discharge opening than the second interconnection opening, and wherein the first interconnection opening has a size smaller than the second interconnection opening.