Patent ID: 8864129

Claim:
A sheet processing apparatus comprising: a stacking unit configured to stack a discharged sheet; an alignment unit configured to align sheets stacked on the stacking unit by causing a first alignment member and a second alignment member to come into contact with edges of the sheets stacked on the stacking unit; a determination unit configured to, in a case where a second sheet which has a width that is different from a width of a first sheet stacked on the stacking unit is to be stacked on the first sheet, determine whether or not the alignment unit is to apply an alignment process to the second sheet; and a controller configured to in a case where the determination unit determines that the alignment process is not to be applied to the second sheet, perform control to stack the second sheet on the stacking unit and control the alignment unit not to apply the alignment process to the second sheet, and in a case where the determination unit determines that the alignment process is to he applied to the second sheet, perform control to stack the second sheet on the stacking unit and cause the alignment unit to apply the alignment process to the second sheet.