Abstract: In order to study the stage feature of coal during the low temperature oxidization process and the coal dynamics features at different stages, the gas chr omatograph were applied to measure the CO density occurred from the oxidation of coal sample under different temperature and under the condition of the programmed temperature rising.The study found the polynomial relationship between CO density and temperature, which could be the coal oxidization reaction function model.The fit . ting sectionally conducted with the dynamics analysis integral method found that between 30 °C and 80 °C，the coal sample would not heave linear relationship and fttin g effect was poor.When the temperature was between 80。C and 200 °C, the ftting of the coal sample would be over 0.99 and ftting effect would be good.The study res ults showed that in the low temperature oxidization process, before and after the critical temperature reached, not only the dynamics parameters would have difference and the one reaction function model could not be fully to explain the reaction mechanism.