This paper describes the initial idea of building up a new approach of spectroscopic ellipsometry for studying electrochemieal reaction from some of the author's experimental results on ellipsometry. The results which have proved the possibility of this idea is also presented. The study on an odic oxidation of iron and the oxidation and reduction processes of polyaililine film by ellipsometry with different wavelength show that the ellipsometric spectroscopy might be a new method for analyzing electrochemical reactions.