The electrochemical polymerization of monomers of pyrrole,rnthiophene, and aniline on platinum and glassy carbon electrodesrnwas carried out with dc cyclic voltammetric technique. Thernoxidation peak potentials for both the monomers and the polymerrnfilms in different base electrolytes were determined by usingrndc cyclic voltammetry. The redox reversibility of equimolarrnconcentrations of the (Fe (CN) 61 4-/3- couple in 0.1 M KCl onrnpolymer coated electrodes has been compared with that on barernplatinum and glassy carbon electrodes with dc cyclicrnvoltammetry. The polymer coated electrodes have shown widerrnpeak separations compared to the bare electrodes. Higher orrnlower peak currents were observed for the redox reaction ofrn(Fe(CN)6 14-/3- systems in 0.1 M KCl depending upon the type ofrnpolymer films and the nature of base electrolytes used in thernelectrochemical polymerization process.rnThe diffusion coefficients of [Fe(CN)614- and [Fe(CN)6l 3- inrn0.1 M KCl were evaluated on polymer coated electrodes fromrnrotating disk electrode experiments. The results were comparedrnwith the diffusion coefficients of these electroactive speciesrnon bare platinum and glassy carbon electrodes. These results onrnthe bare electrodes are in good agreement with literaturernvalues. Attempts have also been made to correlate therndiffusion coefficients of [Fe(CN)61 4-/3- systems on polymer coatedrnelectrodes with the type of polymer film and the nature of basernelectrolytes.