In order to analyze the thermal decomposition of MT based pyrolant in nitrogen and air environments,the thermal analysis experiments of MT and MTV pyrolants were carried out by TG-DTA and DSC.The results show that,in nitrogen environment,the spectrum result of Grignard-type reaction[6]is verified by the decomposition characteristics of MT and MTV pyrolants.8.71%of Mg is consumed in the intermediate reaction of MT at 500-596℃and the heat release of reaction is 31.93 kJ/g.The endothermic decomposition of the intermediate product is at 684-740℃.In MTV,the intermediate reaction is at 435-595℃and the heat release of reaction are increased by the addition of fluororubber.The intermediate product degrades at 677-745℃.In air environment,the decomposition of MT and MTV show the different reaction mechanism from the nitrogen environment.The presence of oxygen is involved in the reaction of Mg,and inhibits the intermediate reaction process of Mg and PTFE. In order to analyze the thermal decomposition of MT based pyrolant in nitrogen and air environments, the thermal analysis experiments of MT and MTV pyrolants were carried out by TG-DTA and DSC. The results show that, in nitrogen environment, the spectrum result of Grignard -type reaction [6] is verified by the decomposition characteristics of MT and MTV pyrolants.8.71% of Mg is consumed in the intermediate reaction of MT at 500-596 ° C and the heat release of reaction is 31.93 kJ / g.The endothermic decomposition of the intermediate product is at 684-740 ° C. In MTV, the intermediate reaction is at 435-595 ° C. and the heat release of the reaction are increased by the addition of fluororubber. The intermediate product degrades at 677-745 ° C. In air environment , the decomposition of MT and MTV show the different reaction mechanism from the nitrogen environment. The presence of oxygen is involved in the reaction of Mg, and inhibits the intermediate reaction process of Mg and PTFE.