The anodic oxidation of tantalum in the gas phase was studied using an electromagnetic, ion cathode. The anodic films were prepared at constant current densities of 1.0 and 2.0 ma/cm2. The growth characteristics of anodic tantalum oxide films, in the gas phase, were found to be similar to films prepared in liquid electrolytes. A comparison is made between the results of this study and other reported gas phase reactions with various anode surfaces. The tantalum oxide growth, for the experimental conditions reported here, is shown to be linearly dependent on the total charge passed in the anode circuit during the reaction up to a formation voltage of 200v.