Abstract: The pyrolysis characteristics of Shuozhou long flame coal were studied using TG-MS online coupling technology and orthogonal experimental method. The experimental results indicate that the pyrolysis process of the experimental coal sample is an exothermic reaction, mainly affected by the heating rate. As the heating rate increases, the weight loss peak and the temperature at the beginning of pyrolysis shift towards the high temperature zone. The particle size determines the conduction velocity of heat inside coal particles, indirectly affecting the release of pyrolysis gases. Increasing the O2 content appropriately is beneficial for coal pyrolysis. For different pyrolysis products, the required conditions are not the same, and the actual production process should be adjusted appropriately according to the pyrolysis products.