In the process of silica(SiO₂) sol transiting into gel, the definite mixture of acetone, N,N-dimethylformamide(DMF) and hexogen(RDX) and the mixture of acetic ester and fluorine rubber(FPM₂₆₀₂) were added sequentially, and the sub-transparent white 80% RDX/SiO₂ booster membranes were obtained by pulley and manual spin coating methods. Results show that when the molar ratio of silicic acid tetracthyl ester (TEOS) to ethanol is 1：4, with the proper decreasing of the molar ratio between ethanol and water, the ductility of membrane and the particle size of RDX decrease. When the sol ages at 60 ℃, the viscosity of sol solution increases from 3 Pa·s to 13 Pa·s at gel point with the increasing of aging time, and the membranes acquired by spin coating is thin and smooth. The SEM photographs show that the spheroidal SiO₂ with particle size of 300-500 nm adheres on the surface of RDX and forms a blocklike composite membrane element of RDX/SiO₂ with size of 3-5 μm,which is a new-type booster membrane.