Abstract: Spontaneous combustion of coal is a serious threat to the safety production pocess of coal mine,the traditional technology of coal spontaneous combustion control such as grouting in not good.Mud foam is a new type of fire-fighting material,and the influence factors,major-minor sequence of factors and optimum proportion of mud foam preparation were investigated in this paper.Research results shows that the influence on foam volume is in the descending order of surfactant concentration,stabilizer concentration and mud concentration,while the influence on stable time is in the descending order of mud concentration,stabilizer concentration and surfactant concentration.Meanwhile,the inhibition property of mud foam is measured through the programmed temperature test.The release amount of CO,CH4 of coal samples treat with mud foam at temperature of 200 C decrease by 49.7% and 35.1%,respectively,compare with that of raw coal samples.Hence,the mud foam with good inhibition property can effectively coal oxidation and the release of CO,CH4.