The incorporation of EDTA and Fe(II/III)EDTA into polyaniline films has been achieved by electropolymerization of aniline in acid solutions at constant potential. The stability and electrical properties of these films have been studied by cyclic voltammetry and electrochemical impedance spectroscopy. The presence of FeEDTA species inhibits the second redox process in the polymer film corresponding to the emeraldine/pernigraniline transition and decreases degradation of these films upon cycling to positive potentials. EDTA increases the degree of cross-linking reactions within the film and leads to less conducting and thinner films compared to those obtained with FeEDTA in the electrolyte.