An ambient-cured epoxy modified organosilicone resin was synthesized by copolymerization using lab-synthesized polysiloxane resin and biphenix-A epoxy resin (E-20).The effect of weight ratio of polysiloxane resin to E-20,reaction temperature and reaction time on heat resistance and miscibility etc were discussed in detail.The experiment results showed that the epoxy modified organosilicone resin exhibited the best miscibility and adhesion strength when the ratio of the polysiloxane resin to E-20 was 3∶7.The optimize polymerization process was kept reaction temperature at 180-190 ℃ for 2-3 hours.