In order to enhance the compatibility of α-AlH₃ with HMX and CL-20， silane coupling agents with different organic functional groups were used to coat α-AlH₃. The structure and morphology of α-AlH₃ were characterized by X-ray diffractometry （XRD）， infrared spectroscopy （FT-IR）， X-ray photoelectron spectroscopy （XPS） and scanning electron microscopy （SEM）， and the compatibility of α-AlH₃ and modified materials with HMX and CL-20 were investigated， respectively. The results showed that the silane coupling agent could form a uniform cladding layer on the surface of α-AlH₃ without changing its native structure. γ-thiopropyl triethoxysilane （KH580） coating improves the thermal stability of α-AlH₃， increases the maximum thermal decomposition temperature by 1.7 ℃ and increases the activation energy E_a value by 2.21 kJ·mol^-1. After the modification of KH550 and KH570 ， the compatibility of α-AlH₃ and HMX hybrid system increased from level 3 to level 1. After the modification of KH550， the compatibility of α-AlH₃ and CL-20 mixed system is increased from level 4 to level 1.