An image forming apparatus is disclosed wherein an image reading portion is provided in spaced relationship with a top surface of an image forming portion. Further, in the apparatus: a supporting column portion is standingly provided on the image forming portion for supporting the image reading portion in a cantilevered manner; a tubular duct portion is provided inside the supporting column portion with an axial direction being substantially a vertical direction; an exhaust port is provided at the supporting column portion for exhausting air of the duct portion; and an intake port is provided below the exhaust port for delivering air from inside the image forming portion to the duct portion.