Abstract: In order to study the effect of oxygen consuming inhibitor on inhibiting coal spontaneous combustion,on the basis of oxygen consumption test and taking CO volume fraction as the index of optimization,the experiment of inhibi- ting coal spontaneous combustion was carried out. Research shows that the oxygen consuming inhibitor not only has a good effect of oxygen consumption,but also has a better effect on inhibiting coal spontaneous combustion when oxygen agent is added into inorganic salt inhibitor. The better effect of oxygen consumption,the better effect of inhibiting coal spontaneous combustion. The oxygen consuming inhibitor which has the best effect on inhibiting coal spontaneous com- bustion was selected by experiment,which is composed of 1. 5 g reduced iron powder,0. 6 g diatomite and 0. 15 g MgCl2 . The resistance efficiency increased by more than 43. 8% comparing to inorganic salt. In a certain range,the higher the temperature,the better resistance effect of inhibitor with oxygen consumption effect. The smaller particle size of coal sample,the worse effect of resistance of oxygen consuming inhibitor. When the coal particle size decreases to 80 mesh,with any further reduction of coal particle size,the effect of inhibiting coal spontaneous combustion has no obvi- ous difference.