Abstract: To investigate the oxidation combustion heat effect and thermokinetic behavior of lean coal, the pulverized coal samples were tested using C80 micro caloric system and thermogravimetric experimental device, respectively. The thermal effects of lean coal samples during the low-temperature oxidation and oxidation combustion were analyzed, and the influence of the heating rate on the combustion process of lean coal was also studied. In addition, the apparent activation energy and the most probable mechanism function of the coal sample during the combustion process were analyzed. The results indicated that the low-temperature oxidation process of lean coal pulverized coal could be divided into slow oxidation, accelerated oxidation and fast oxidation stages. Moreover, the five characteristic temperature points during the oxidation combustion of pulverized coal were determined by the variations of TG/DTG curves; with the increase of the heating rate, the TG and DTG curves of the coal sample shifted to the high temperature zone, and the peak value of the DTG curve increased with the ignition temperature increased; the apparent activation energy of coal sample in the pyrolysis combustion stage described a trend of first increasing and then decreasing with the increase in the conversion rate. The maximum apparent activation energy were observed when the conversion rate is 0.2, which was 32.4 kJ/mol; heating rates had tiny effect on the most probable mechanism function of the oxidation reaction. The most probable mechanism functions of the reaction under the four heating rates were all basically in line with the A-E equation random nucleation and subsequent growth model, and the peak value of the function curve increased with the heatingrate increased.