Patent ID: 8346155

Claim:
A sheet processing apparatus, comprising: a sheet conveyance portion configured to convey a sheet to a sheet abutting member against which an edge in a sheet conveyance direction of the sheet is abutted; a punching unit including a plurality of punches arranged in a width direction perpendicular to the sheet conveyance direction and die holes that are cooperative with the plurality of punches to perform punching processing on the sheet, the edge of which passes through the die holes and is abutted against the sheet abutting member; a shifting unit configured to move the sheet in the width direction; and a control portion configured to control the shifting unit based on information indicating a sheet length in the width direction of the sheet to be conveyed to the sheet abutting member so that the shifting unit moves the sheet in the width direction by a predetermined amount that is set so as not to overlap a corner portion of the sheet with any of the die holes.