Abstract: The invention relates to a cutting knife for rotary cutting installations for printed products or webs of flexible materials such as paper, plastic, fabric, leather or wood, especially multi-layer paper products that are separated in a tiled arrangement. Said cutting knife has a substantially circular, discoid cutting base having an axis of rotation which is substantially disposed in the center of the disk, and cutting sections at the edge of said base. The cutting sections have at least two different alternating areas. The first area is configured as a kind of saw tooth by notching the cutting base and the second area is configured as a kind of paring knife and extends conically towards the edge of the cutting knife relative to a width of the cutting base. The cutting base, in the second area, has an at least partially larger radius than in the first area.