The purpose of the present invention is to provide a sheet bundle binding processing apparatus capable of performing a binding process on a sheet bundle inserted to a manual setting portion of an apparatus housing and a binding process on a sheet bundle introduced to a processing tray with a common stapling unit having a simple unit moving mechanism therefor as well as facilitating staple replenishment. The present invention comprises a sheet bundle binding processing apparatus including a processing tray on which sheets are stacked, a binding device which staple-binds a sheet bundle stacked on the processing tray, and a manual setting portion to which a sheet bundle is set from the outside of the apparatus, the binding device being arranged to be movable among a first position where a sheet bundle stacked on the processing tray is to be bound, a second position where a sheet bundle set at the manual setting portion is to be bound, and a third position where staples are replenished to the binding device.