An image forming apparatus includes a guide member including a guide surface that guides a sheet to a delivery rotating body, an opposing member opposed to the other face of the sheet, on an opposite side of the guide surface of the guide member, and defining an air passage between the opposing member and the guide member, such that one end portion is located on a side of the outer space, and the other end portion, on an opposite side of the outer space, communicates with a predesignated space on a side of the fixing device in an apparatus main body, and a dam member located downstream of the delivery rotating body in a sheet transport direction, and configured to dam air to be discharged with the sheet by the delivery rotating body, thereby guiding the air to the one end portion of the air passage.