The electro-oxidative degradation of polyaniline films electrodeposited on the platinum electrode has been studied using radiotracer and potentiodynamic pulse techniques. It was discovered that the surface of the platinum electrode had been covered by polymer chains and is released from them and obtains the ability for adsorption of hydrogen and other particles (eg, aniline) on released platinum centres. At low potentials such type degradation is not accompanied by mass and doping peak changes. These changes take place at higher potentials of degradation. It was found that aniline monomer units of all layers of film are removed from the polymer at high potentials of degradation.