Abstract: A shredding apparatus is disclosed, which comprises rotary cutting disks and back plates. The rotary cutting disks each have peripheral edges serving as blades. The rotary cutting disks serve to shred sheets in the direction in which they are withdrawn. The rotary cutting disks each have large tooth portions formed on the outer periphery at a uniform circumferential spacing for co-operation with a back surface of the associated back plate to cut the sheets in the direction perpendicular to the direction of their withdrawal, they also each have small tooth portions formed on the outer periphery between adjacent large tooth portions, the small tooth portions being co-operative with the back surfaces of the associated back plates to compress chips produced as a result of shredding.