A copying machine having a two-in-one copying mode has a pickup roller 65, a separating roller 75, a register roller 90, a conveyor belt 95 and a pinch roller 101. The pickup roller 65 and the separating roller 75 feed a document toward a glass platen 29 one by one to stop the document at a first-out position. The register roller 90 conveys the document fed by the pickup roller 65 and the separating roller 75 onto the glass platen. The conveyor belt 95 conveys the document conveyed by the register roller 90 along the glass platen 29 until a rear end of the document reaches a predetermined switch-back position, then conveys the document in the opposite direction to retreat a predetermined distance, and then conveys the document as well as a succeeding document stopped at the first-out position such that a front end of the document situated on a downstream side of the document conveying direction may be aligned with an exposure reference SP, and then discharges the documents to the downstream side of the document conveying direction after exposure. The pinch roller 101 conveys the documents discharged by the conveyor belt 95 from the glass platen 29 to a discharge section 115.