A kind of hybrid of silicon-phosphorus was prepared via the hydrolysis and polycondensation reaction of silica sol and phosphorus-containing silicon coupling agent which was synthesized by 3-glycidoxypropyl trimethoxysilane and phosphoric acid. A cured epoxy resin containing hybrid of silicon-phosphorus was prepared by the in situ curing of the bisphenol-A type epoxy resin and 4,4'-diaminodiphenylmethane with the hybrid of silicon-phosphorus. Determinations of differential scanning calorimetry, thermogravimetric analysis, limited oxygen index and tensile testing were carried out to characterize the cured products. The results showed that the limited oxygen index of the curd epoxy resin containing hybrid of silicon-phosphorus was 28.2, Tg=178℃, higher than those of pure epoxy resin by 25% and ,18℃, respectively. The residual char yield under 700℃ and the temperature of 50% weight loss increased, but the tensile strength descended rarely. Compared to the pure epoxy resin, he cured epoxy resin containing hybrid of silicon-phosphorus possessed flame resistance and the thermal properties were improved.