The image forming apparatus includes two tension rollers; a conveyor belt movably supported at the two tension rollers; a plurality of transfer parts that are arranged on the back surface side of the conveyor belt and between the two tension rollers, that contact one surface of the back surface of the conveyor belt, and that form a predetermined clearance with an opposite portion of the back surface of the conveyor belt; and a cleaning blade for removing residual toner remaining on the conveyor belt. The cleaning blade has the front end contacting the conveyor belt at a predetermined pressure. The cleaning blade is arranged at a position where the back surface of the conveyor belt distorted by the front end does not contact the tension roller.