Abstract: The basic principle of ellipsometry, the technical problem applied it to the corrosion study have been introduced. By means of ellipsometry and ellectrochemical measuring techniques, the kinetics formed the passive film in the crevice on stainlees steel has been stadied. The result shows that process of operation is easy, although the basic principle of ellpsometry and calculation method is complicated. Ellipsometry has advantages over conventional techniques of application to the measurement in the surface film on corrosion metals in situ.