Hydrogen peroxide and UV radiation have been used in the photochemical degradation of isoprene in aqueous solutions. A kinetic study is carried out taking into account the contribution of the UV radiation reaction and the combined reaction with hydrogen peroxide. An empirical reaction rate expression, which considers the two reactions taking place in parallel, is suggested. Pseudo-first order rate constants are obtained from batch reactor data, As the molar ratio of H2O2:isoprene increases, the rate of reaction increases linearly while the concentration of H2O2 is observed to be nearly constant throughout the reaction; suggesting that the H2O2 acts as a pseudo-catalyst. Nearly complete oxidation of isoprene is achieved. These results indicate that the H2O2/UV process appears to be a competitive alternative destructive treatment for removing isoprene from water present at low levels.