PURPOSE: To enable blanking of disks with high accuracy at a high speed by first blanking outer peripheral parts out of a substrate, then blanking inner peripheral parts.

CONSTITUTION: First, the outer peripheral parts of patterns are blanked. For example, 10 sheets of replicas are blanked simultaneously by one time of stroke. The relative positions of 10 sets of punches and dies are preset and fixed. The disks 3 blanked only at the outer peripheries are blanked by one sheet each to form optical disk products 4. Then, the disks are cut out of the transparent substrate 1 on which the optical disk patterns 2 are reproduced.