Amorphous oxide films have been grown on Zr, Ti, W, Ta, Nb, and V by ionized gas anodization using the ion cathode as a source of negative ions. Films were grown on each metal at constant current to 175V followed by constant voltage for about 4 hr. Several electrical and optical properties were measured for the anodic films produced on these refractory metals. Resistivities of the anodic oxide films on Zr, Ti, W, Ta, Nb, and V ranged from 1014 to 1017 ohm‐cm. Breakdown voltages with the refractory metal positive (gold contact negative) were of the order of 31V to 111V. Film capacitances for these metals varied between 0.031 and 0.050 µf/cm2, and the dissipation factors averaged 0.015 for all the oxides except V which was 0.062. Thicknesses and refractive indices were obtained by ellipsometry for anodic films on Ta and Nb. Film thicknesses were respectively 0.61µ and 0.57µ for Ta and Nb whereas the refractive indices were 2.1 and 2.0. Dielectric constants calculated from capacitance measurements for these anodic films were 22 and 28, respectively. The properties of films prepared by the ion cathode method are compared with those produced by plasma and solution methods reported by others.