To provide a formation method for an antenna conductor pattern of a radar antenna for millimeter waves which enables formation of a high-precision antenna conductor pattern on the internal surface of a plastic molding which curves with a specific curvature.

A parabolic plastic molding 10 having predetermined curvature is manufactured by plastic molding. On the internal surface of the plastic molding 10, a plated underlying layer is formed by electroless copper plating or the like. Using the plated underlying layer as a cathode, electrolytic copper plating is performed, and a conductor layer 21 of copper of specified thickness is formed. Moreover, the conductor layer 21 is worked into a conductor pattern 21a by a laser of a wavelength of 532 nm. Furthermore, a nickel layer of predetermined thickness is formed on the surface of the conductor pattern 21a, to obtain a radar antenna 20 for millimeter waves.