An image forming apparatus for forming an image on a sheet, includes: an image forming section which forms the image on the sheet; a fixing device which fixes the image onto the sheet; a first duct which covers the fixing device and ventilates air heated by the fixing device; a second duct, which covers the first duct and ventilates cool air introduced from outside; and an exhaust fan which exhausts the air that has passed through each of the first duct and the second duct.