In order to evaluate the thermal safety of hydrazine compounds gel propellant,its thermal decomposition characteristics were studied by Differential Scanning Calorimetry(DSC) and Accelerating Rate Calorimeter(ARC). The onset decomposition temperature of propellant are 185.73, 227.20, 230.37 and245.19℃ in different heating rate of 2,5,10 and 20K·min-1,respectively in DSC test and the activation energy of the gel propellant is 181.80 k J·mol-1according to Kissinger method. Whilst in ARC test,in the ideal adia...