UV-Vis absorption spectrum and cyclic vohammetry were adopted to study the influence of o,m,p-phenylenediamine monomers on the polymerization rate of aniline and the degradation process of PAn films,respectively．The results showed pPDA accelerated the polymerization of aniline and the degradation of PAn films,while oPDA and mPDA both restrained the polymerization and the degradation．A possible Feason for this phenomenon was that the different structures of phenylenediamine affected the polymerization mechanism and changed the chemical physics pmperties of PAn films to a certain extent SEM images displayed that the films becattle more compact and smoother compared with pure PAn films,which indicated the addition of phenylenediamine fiqononmers also had an apparent influence on the morphology of PAn films．