Abstract: This paper compare the changes of O2, CO and activation energy of five kinds of Se Lian coal samples under different air flow by temperature programming. The experimental result indicated that the oxygen consumption of 0-0.9mm small size coal sample more sensitive about the air flow change, and small size coal sample with low air flow rate have minimum activation energy. Different air flow will rise a turning point of CO production rate at the cracking temperature about 120℃. This paper have a positive instruction to determinate the coal spontaneous combustion and the air flow rate of coal at low temperature oxidation experiment.