The invention relates to a cutting rotor (1) for granulating plastic castings, provided with cutters (4), which axially project from the face of the cutting rotor and which are individually fastened to supporting surfaces of the cutting rotor (1) by means of fastening elements (12). The supporting surfaces are delimited by the lateral walls (8, 9) of radial slots (7) in the peripheral surface (2)of the cutting rotor and by radial transverse walls (10, 11), inside of which the cutters (4) are, with a projection (6), inserted in a hook-like manner. One side of the projection (6) forms an abutment (18) for the fastening element (12) that passes through a radial transverse wall (11) and presses against the abutment (18).