Method of manufacturing circuit on sheet metal

The invention relates to a method of manufacturing circuits on sheet metal. The method comprises the steps of: coat-plating a polymer thermal conductive insulating layer on a metal radiating fin to form a substrate capable of radiation, and manufacturing a sheltering jig corresponding to a circuit image by adopting a sheltering method according to a designed circuit; and coating the sheltering jig on the polymer thermal conductive insulating layer of the sheet metal, conducting vacuum magnetron sputter coating on the sheet metal, taking the sheltering jig away so as to leave a conductive circuit on the insulating layer, and adopting an electroplating process on the basis of the conductive circuit to increase the metal layer thickness of the circuit. By adopting the method of manufacturing circuits on the sheet metal, the polymer thermal conductive insulating layer is painted on the original sheet metal, the insulation effect is achieved, the substrate capable of effective radiation is formed, the vacuum magnetron sputtering technology is adopted, the manufacturing yield, stability and safety of the entire manufacturing process can be greatly increased, the manufacturing steps are shortened, the manufacturing procedure is simplified, and the environmental pollution is reduced.