The kinetics and mechanism of ozone oxidation of 2-nitrotoluene dissolved in glacial acetic acid solution was studied. The addition of transition metal salts to the system was shown to increase the selectivity,of oxidation at the methyl group from 8.3 to 75.2%. 2-Nitrobenzoic acid was formed as the main product. The use of a mixed cobalt-bromide catalyst makes it possible to increase the oxidation rate and to significantly decrease the concentration of cobalt diacetate.