In the present work, the oxidation of manganous and chloride ions on a mixed metal oxide (MMO) anode from a 40oC electrolyte containing 160 g/L sulfuric acid (H2SO4) with various concentrations of Mn2+ and Cl- was studied using cyclic voltammetry. These results indicated that Mn2+ concentration does not affect Cl2 evolution on a non-MnO2 coated MMO anode. However once MnO2 deposits on the MMO anode, Cl2 evolution is inhibited. The effects of manganous concentration and chloride concentration on the amount of MnO2 deposited in one hour were also evaluated. Clconcentration did not affect the amount of MnO2 generated. Increasing Mn2+ concentration resulted in an increase in the amount of MnO2 deposited.