The adsorption and oxidation of benzene in acidic media on platinum electrodes (polycrystalline and single-crystal electrodes) have been studied by cyclic voltammetry and in-situ Fourier transform infrared spectroscopy. The oxidation characteristics of benzene depend on the surface structure of the platinum electrode used. In all platinum electrodes studied, the main reduction product of benzene is: cyclohexane, and the oxidation products detected by infrared spectroscopy have been CO2 and benzoquinone. Pt(100) is the surface more active for the oxidation of benzene to CO2 and Pt(110) is the surface more active for the reduction of benzene to cyclohexane.