Patent ID: 8132803

Claim:
A sheet processing apparatus which processes a sheet after aligning the sheet, the sheet processing apparatus comprising: a conveyance portion which conveys the sheet; a stacking portion on which the sheet conveyed by the conveyance portion is stacked; an alignment reference member on which end portions, in a width direction perpendicular to a sheet conveyance direction of the conveyance portion, of the sheets conveyed to the stacking portion are abutted to align the sheets; an alignment member which is (1) moved from a first standby position toward the alignment reference member to align a first-size sheet having a first length in the width direction, and (2) moved from a second standby position, which is closer to the alignment reference member than the first standby position, toward the alignment reference member to align a second-size sheet having a second length in the width direction smaller than the first length in the width direction; a stapler which performs a stapling process of stapling the sheets with a staple having two staple legs; and a controller which controls movement of the alignment member, wherein the controller controls the movement of the alignment member based on information that the sheets to be aligned are the first-size sheets so that the alignment member is moved to align the first-size sheets from the first standby position toward the alignment reference member, by a distance which, even if the sheet conveyed to the stacking portion is the second-size sheet, allows the stapler to staple the sheets moved by the alignment member with at least one of the two staple legs.