The electro-optical behaviour of a platinum or gold electrode covered with thin polyaniline (PANI) films has been studied using electroreflectance (ER) and differential reflectance (DR) techniques. Depending on the electrosynthesis procedure a drastic polarization selectivity in the red part of the optical spectra has been observed. This effect was shown to reflect a great extent of the orientation of PANI chains perpendicular to the electrode surface.