An image forming apparatus includes a feeding unit, an image forming unit, a reading unit, a conveyance unit, a first discharge unit and a second discharge unit, a determination unit, and a control unit. When an (n)th sheet in a first copy is an abnormal sheet, remaining sheets include sheets fed by the feeding unit after the abnormal sheet is fed by the feeding unit until the image on the abnormal sheet is read by the reading unit, and the remaining sheets include a first group of remaining sheets and a second group of remaining sheets. The control unit is configured to execute an abnormal discharge mode in which the sheets of the first group of the remaining sheets are discharged to the second discharge unit and each of the sheets of the second group of the remaining sheets is discharged selectively to the first or the second discharge unit.