The anodic deposition of iron oxide films on passive iron polarized at +300 mv in boric acid/sodium borate solutions, at pH 7.52, containing ferrous ions has been investigated. The deposition takes place with a current efficiency of 100% based on the reaction . The kinetics of the anodic deposition could be divided into two consecutive regions, an initial stage characterized by the formation of a film with the thickness of a unit cell, followed by a steady growth region where the rate of deposition is dependent on the ferrous ion concentration in the solution and the oxide layer thickness. Both the anodic current densities and the cathodic reduction behavior indicate that the deposited iron oxide film is different from the film formed by anodic oxidation of metallic iron in terms of both electronic conductivity and chemical composition.