Semiconducting TiO2 has some photoelectrochemical reactions under ultra-violet irradiation. These photoelectrochemical behaviors studied as possible protection from corrosion. TiO2 thick films were prepared on stainless steel by plasma-spray coating. The film thicknesses were 50∼100μm. The films were characterized by X-ray diffraction, and the diffraction patterns clearly showed a rutile type structure. The crystallization of the films depends on the spray coating conditions. We have investigated the protection properties of the films by measuring the electrode potential. The electrode potential of the films were reduced by about 250m V under ultra-violet irradiation. This potential drop value is sufficient for protection from the corrosion.