The oxidation of methanol and Cl molecules at electrodes modified with polyaniline and particles of platinum and ruthenium has been studied in aqueous HClO4 electrolyte. The platinum and ruthenium particles were incorporated into the polyaniline film by electrochemical reduction. The activity for the oxidation of Cl molecules is higher for bimetallic electrodes than for polyaniline-coated electrodes modified with platinum alone. Indeed, a negative shift of more than 100 mV is observed as compared to the potential obtained with a polyaniline film modified by pure platinum. Moreover, the oxidation of methanol is faster and more complete on the Pt-Ru modified polyaniline electrode, since carbon dioxide is the main reaction product.