Simple inverting path for an auto document feeder for an image forming apparatus

A document setting tray of the ADF is disposed above a platen glass of an image forming apparatus. A duplex document ejecting tray is disposed above a document setting tray. A switch back table, on which the duplex document is switched back after one side thereof has been read by the reading device and fed again toward the image reading device, is disposed between the document setting tray and the duplex document ejecting tray. A switch back return path is disposed between the reading position of the image reading position and the switch back table.