Nanosized TiO2 films on stainless steel were prepared by electrophoretic deposition and characterized by X-ray diffraction analysis and photo-voltammetry. The decoloration of methylene blue (MB) dye was used as a test reaction for the evaluation of photoelectrocatalytic activity of the prepared TiO2 coatings. The influence of applied potential and potassium peroxodisulfate on the rate of MB decoloration was investigated. The possible mechanisms of MB oxidation under various experimental conditions are discussed.