The mixed louver spiral fin is a development of the conventional spiral fin-and-tube heat exchanger having louvers at the surface of the fin. Louvers are made on the fin surface for enhancing heat transfer performance. The louvers made are perpendicular and parallel with the radius of the fin. The mixed louver spiral fin can be used for building heat exchangers with heat exchange between fluids, such as gas, liquid, or gas-liquid two phases or application in heat exchangers for waste heat recovery.