A H2-02 fuel cell system was applied for the synthesis of cresols from toluene. Partial oxidation of toluene was initiated by an active oxygen generated on the cathode during H2-02 fuel cell reaction. The selective oxidation of toluene to cresols has been effected by using the cathode of carbon black and diluted electrolyte (to.5 M. H3PO4). The cathode of active carbon added with FeC13 was also favorable for the synthesis of cresols. The mixture of carbon whisker and FeClg-added active carbon enhanced the rate of cresol formation. Cresol is an important chemical used In the manufactures of plastics, pesticides, disinfectants, etc. Synthesized cresols are produced by the Cymene Process which requires multi-step operations throughout the whole process for converting toluene to cresols. The conversion of toluene to cresols in one step by partial oxidation using oxygen must simplify the process and save energy. We have reported that the oxidation of benzene to phenol can be carried out at room temperature applying an H2-02 fuel cell system (l-2). The oxidation of toluene by this technique produced a mixture of cresols, benzaldehyde(PhCH0) and benzylalcohol(PhCH20H) (l-3). Recently, we have found that the formation of cresols with high selectivity can be realized by modifying the cathode under appropriate reaction conditions. Therefore, we report here a new technique for the synthesis of cresols from toluene using the H2-02 fuel cell system.