The oxidation kinetics of benzhydrol and para-chlorobenzhydrol involving rare earth compound selenium dioxide as an oxidant in acetic acid-water medium in presence of H₂SO₄ have been studied in order to probe better reaction mechanism. The reactions obey first-order kinetics in [SeO₂] and [substrate] and sensitized to H+ ions. The ionic strength on rate of reaction has nominal effect. An increase in rate with increasing percentage of solvent was observed. ~I and + mesomeric effects dominate the order of reactivity in conformity with Arrhenius parameters.