A sheet binding processing apparatus including a processing tray, a sheet positioning device, a first binding device, a second binding device, a driving device which moves the second binding device to a binding position where the sheets positioned by the sheet positioning device are to be bound and to a retracting position for retracting to the outside of the sheets positioned by the sheet positioning device, and a controller which controls the driving device and causes the second binding device to be located at the retracting position when the first binding device binds sheets.