Platinum dispersed in a polyaniline him is a better catalyst than smooth Pt for ethylene glycol electrooxidation in perchloric acid aqueous solutions. The catalytic activity of the platinum microparticles is further enhanced when Ru, Sn or both are codeposited. The PAni/Pt-Sn assembly shows the highest electrocatalytic activity of the electrodes examined. Underpotential deposition of Tl and Pi on dispersed Pt inhibits EG electrooxidation while Pb causes significant catalysis only with a specific preparation method electrocatalyst. The morphology and the identity of the metallic dispersion is examined by transmission electron microscopy.