To provide a device with a simple mechanism capable of certainly performing sorting in the device for sorting and piling up conveyed paper sheets.

In the sorting device 6 for sorting and piling up postcards 50 delivered from a delivery roller 70 on a stacker 85, a shaft part 90 perpendicular to a placement surface of the stacker 85 for placing the postcards 50 and a driving mechanism 93 for rotating/driving the stacker in a left/right direction making the shaft part 90 as a center are provided. The stacker 85 is rotated in the left/right direction in every predetermined sheets to sort the postcards 50.