Abstract: A notch forming device, comprises a notch forming section to form a notch on an edge of a sheet constituting a sheet bundle to be outputted in accordance with an execution of a job; a shifting section to shift a position of a notch to be formed on a sheet by the notch forming section; and a control section to control the shifting section. When plural sheet bundles are outputted in accordance with the execution of the job, the control section controls the shifting section to make a position of a notch on a leading sheet of each sheet bundle at the same position.