The present work confirmed and achieved the relevant parameters which belong to the manganese nitriding model via experiments. Based on the metallic iron nitriding model and the nitride layer growth model, metal manganese nitrding model was set up. The change laws between the kinetic parameters and temperature of the solid metal manganese nitriding model was studied by using the optimum method. The experimental results showed that the ratio of weight gain for samples relatively increased with the increasing of nitriding temperature, and the results obtained from the numerical model indicated that the kinetic parameters of manganese nitriding model increased with the increasing of nitriding temperature.