High strength center lock structure, which can provide strong braking force even during intenses cycling and avoid the influence of rotor stress. The polygonal airflows designs and large hole spacing provide good heat dissipation performances and reduce brake attenuation and warpage, thus ensuring excellent brake performances. The bike disc brake Rotor is make of Aluminum alloy and high carbon steel, with high strength, not easily to deforms, and excellent rusts prevention and wear resistance. Used as front disc brake bike and rear disc brake bike, easily to install. Excellent dry and wet performances, good wear resistance, quickly ventilation and good heat dissipation.