An automatic document feeder of the invention has a conveying roller for conveying a document sheet to a document reading position on a platen facing a document image reading portion. The automatic document feeder contains a pickup guide for picking up the fore end of a document sheet scanned at the document reading position and a pressing piece for pressing a document sheet being conveyed against the pickup guide at a curved portion provided by the platen and the pickup guide. The pressing piece is fixed at an upstream side of the document reading position, extending from the fixed position across the document reading position and is made free at a downstream portion. Further, this document feeder is provided with a document sheet deflecting device for deflecting a document sheet toward a paper discharge stacker. The document deflecting device is a plate spring being capable of swaying within a specified range.