The kinetics of oxidation of salicylic acid by acidic solution of perchlorate in the presence of Ru(III) as a catalyst have been carried out. The reaction follows almost similar kinetics, being first order with respect to salicylic acid, Chloramine-T and Ru(III). During the reaction, it is observed that there is a inverse first order with respect to perchloric acid (H + ). The addition of p-toluene sulphonamide, which is one of the reaction products, had no significant effect on the reaction rate. Thermodynamic parameters were computed by studying the reaction at different temperature (303 – 318 K). On the basis of experimental findings, a suitable mechanism consistent with kinetic results has been proposed.