Abstract: Based on the kinetics of nitration and oxidation of dinitrotoluene,the steady-state mathematical model is developed for producing trinitrotoluene with o -nitrotoluene in the last-stage nitration process.The industrial process was simulated by using Monte Carlo and Quasi-Newton methods.The kinetic parameters are estimated according to the industrial process data.The results show that trinitrotoluene can be produced with o -nitrotoluene instead of toluene and a higher productivity can be obtained by using the same equipment.The simulation can provide theoretical guidance for innovation of industrial process.