The corrosion resistance behavior of silane agents(SA) for iron based substrate have been studied. A series of detection methods were used simutaneously for effective analysis and monitoring the hydrolysis process of SA films. It consists of the on line FTIR spectroscopy, conductivity measurement, XPS(for structure and component analysis), elliptical spectroscopy(for film thickness analysis) and electrochemical method(for corrosion examination). The results showed that the rational thickness of the SA films was about 82 nm and there were chemical bondings between the iron substrate and SA film, which produces a large amount of silanols in hydrolysis.