A scanning device includes a transparent platen, a scanning module, a sheet-feeding mechanism, a section and a pressing unit. The scanning module is disposed at a scan position and acquires an image of a document through the transparent platen. The sheet-feeding mechanism transports the document in a transporting direction across the scan position. The section is located downstream of the scan position, and has a low point at a level lower than that of an upper surface of the transparent platen. The pressing unit is disposed opposite the section and limits a distance between the document and the transparent platen. A contact portion between the pressing unit and the document is lower than the upper surface of the transparent platen.