Oxidative reactions of phenol and chlorobenzene with electrogenerated Fenton's reagent, Fe2++ H2O2, were investigated. The electrogeneration of H2O2and the regeneration of Fe2+were performed at a graphite cathode. Results are compared for conventional vs. electrogenerated Fenton's reagent. It was found that the conversion of chlorobenzene was substantially greater by the electrochemical method than the conventional system. The rates of H2O2generation were dependent on solution pH; electrogeneration was favored at low pH, while the opposite was the case for the hydroxylation of the organics. The hydroxylation products of phenol with electrogenerated Fenton's reagent included hydroquinone, catechol and resorcinol. For chlorobenzene, a hydroxylated product (p-chlorophenol) and a dehalogenated product (phenol) were obtained. The rates of phenol and chlorobenzene hydroxylation were dependent on pH, and concentrations of F2+and H2O2. Results indicated that the electrochemical system provided an efficient way to regenerate Fe2+