In order to reduce the sensitivity of HMX, HMX/F2602 nano particles were prepared by spray drying,the proportion is HMX:F2602=97:3. The HMX/F2602 nano particles prepared by spray drying method were compared with HMX/Estane5703 and HMX/F2602 which prepared under the same conditions. HMX raw material and HMX/F2602 nano particles were analyzed by SEM, XRD, DSC, and impact sensitivity tester. The results show that the thermal property and the impact sensitivity of HMX/F2602 nano particles were prepared have advantages than HMX/NC and HMX/Estane5703 particles under the same conditions, the HMX/F2602 nano particles were prepared is spherical, the particle size between 0.5 μm~4μm, the crystal remains unchanged,the activation energy of HMX raw materials and HMX/F2602 nano particles were 523.16kJ/mol, 469.89kJ/mol, the critical temperature of thermal explosion were 279.34℃, 279.20 ℃, the characteristicSdropSheights were 17.6cm, 82.2cm.