The invention discloses a TiC/cobalt-based alloy composite coating on the surface of nodular cast iron, and a laser-cladding preparation process and application thereof, belonging to the technical field of laser cladding technology and coating preparation. According to the invention, TiC/cobalt-based alloy composite powder is used as a laser-cladding material, and the TiC/cobalt-based alloy composite coating is preapared on surface of nodular cast iron by using laser cladding technology. TiC accounts for 0 to 30% of the volume of the composite coating material; and the maximum hardness of the coating is 1200 to 1300 HV0.2, more than five times of the hardness of a nodular cast iron matrix. The composite coating is applied to nodular cast iron parts used under severe wearing conditions.