Apparatus for collecting sheets

In a sheet storage apparatus, a shift trajectory between an aligning position on a load surface and a waiting position above the tray is short, and the shift operation does not cause misregistration of aligned sheets, wherein a regulation member strikes and regulates a sheet carried onto the load surface, and a trajectory is set to displace to the regulation member side. The apparatus includes a transport path having a sheet discharge outlet, a tray member disposed on the downstream side of the sheet discharge outlet and having a load surface of sheets, a regulation member disposed in the tray member to regulate an end edge in a transport direction, an aligning member including a side edge engagement surface engaging a side edge in a sheet width direction on the load surface, and a shift section shifting the side edge engagement surface between the waiting position and the aligning position.