SHEET STACKING DEVICE AND POST-PROCESSING APPARATUS

A sheet stacking device includes a discharge port, an alignment wall, a discharge tray, an alignment belt, and a guide part. The alignment wall extends in an upper-and-lower direction below the discharge port. The discharge tray is provided so as to be capable of moving up and down along the alignment wall. The alignment belt with endless is stretched along the alignment wall in the upper-and-lower direction. The alignment belt has an inner circumferential surface facing the alignment wall and an outer circumferential surface with which an upstream edge of the sheet stacked on the discharge tray comes into contact, and circulates at a same speed as the discharge tray in synchronization with the discharge tray. The guide part is configured to be provided between the alignment wall and the alignment belt. With the guide part, the inner circumferential surface of the alignment belt slides in contact.