PURPOSE: To form a metallized film of prescribed color and concentration, by, in forming colored metal film on the surface of a substrate by ion-plating, changing the concn. of reacing gas used, or by changing the evaporation rate of the metallizing material.

CONSTITUTION: In a bell jar 2 are arranged a boat 4 contg. merallizing metal 15, a coil 10, an electrode and holder 6 which holds substrates 14 made of glass or metal. The bell jar 2 is evacuated to a vacuum, and the inner press. is adjusted with inert gas such as He, Ar. Then one or more reactive gas selected from the group constituting of O2, N2, NH3, C2H2, H2S is introduced into the bell jar 2 to regulate the inner press. to 10-4W10-3 Torr. High frequency discharge generated by a power source 11 in such an atmosphere ionizes the gas. Then a metallizing metal 15 such as Al, Cu, Ni, Zn, or Cr etc. is heated by a power source 7 and is evaporated to form a metallic cpd. with the reactive gas, and the metallic cpd. is accelerated by an AC source 8 to ion-plate the substrates 14. The color and the concn. of the metallized metal is changeable freely by the change in evaporation rate of the metallizing metal 15.