The good silicone modified epoxy resin was synthesized when the hydrolysis temperature was 35~40℃, the hydrolysis time was 1~1.5h ,and the hydrolysis ratio was nH2O/ncl=6:1~7:1.IR indicated that the mainly chemical reaction was occurred between hydroxyls of silicone and epoxy resin.The influence of modified and unmodified epoxy resin on mechanical properties, heat-resistant and moisture resistance was studied.The results show that when R/Si was 1.5, the tensile strength was 23.91MPa ,bending strength was 29.24MPa, the impact strenth was 10.02 KJ•m-2 and the temperatrue of 50% weight loss was 431℃,higher than those of unmodified epoxy resin by 3.86 MPa,9.49 MPa,6.18 KJ•m-2 ,30℃,respectively;At the same time,the moisture resistance of modified resin was increased.