Abstract: The analysis of heat transfer situation of pulverized coal before pyrolysis was made inside the blast tube, and a math model was developed and solved with computer. The results show:(l)The situation of heat transfer before pyrolysis (espcially the radiation) is very important for quick pyrolysis of coal, (2) Pulverized coal lower than 300 μm is favorable, (3)The pulverized coal should not be regarded as thin wall.