Patent ID: 8226078

Claim:
A sheet processing apparatus comprising: a holding portion that holds a booklet, which includes folded sheets, by a pair of holding members opposite to each other; a pressing portion configured to press a spine of the booklet held by the holding portion, having a first pressing member and a second pressing member having a thickness, in a thickness direction of the booklet, greater than that of the first pressing member; and a moving portion that moves the pressing member along the spine, wherein one of the first pressing member and the second pressing member selectively enters a gap between the pair of holding members and presses the spine of the booklet held by the holding portion while the one pressing member is moving along the spine so as to deform the spine, and wherein in a case of processing a booklet having a thickness greater than a predetermined thickness, the second pressing member is selected to press the spine, and a pressing amount in a pressing direction of pressing the spine by the second pressing member is greater than that by the first pressing member.