A sheet cutting device, including a cutting blade for cutting a bundle of sheets, while moving in a slanted direction compounded by a direction perpendicular to the surface of sheet and a direction parallel to the sheet surface; a supporting member for supporting the bundle of sheets in the vicinity of a cutting position; a pressing section to press the bundle of sheets against the supporting member in a direction reverse to a moving direction of the cutting blade and perpendicular to the sheet surface, and the pressing section to receive the cutting blade at the time when the cutting blade cuts the bundle of sheets; a cutting blade driving section to drive the cutting blade; a pressing section driving section to drive the pressing section; and a control section to release pressing of the bundle of sheets and retract the cutting blade, after the bundle of sheets is cut.