The silicone rubber composites with antimony trioxide (Sb2O3) and melamine cyanurate (MCA) additive were fabricated. The results of scanning electron microscope are shown that the Sb(2)O(3)and MCA are uniformly dispersed into the silicone rubber (SR). It was found that tensile strength and elongation at break were down to 300% and 5.3 MPa with the increase in MCA content. The flammability of the composite was also studied by limiting oxygen index (LOI) and cone calorimetry test. The results indicated that a 31.5% LOI of the composite was achieved, and the heat release rate and total heat release values of the composite with MCA were apparently reduced compared to that without MCA. Meantime, the retention of elongation and tensile strength keeps good behavior. The time to ignition of the composite with MCA is belonged. The results show that the microstructure of combustion residue of MCA additive is continuous and smooth, and it is a good barrier to isolate combustible gas and oxygen. All these test results demonstrated that the synergistic effect of Sb(2)O(3)and MCA successfully enhanced the flame-retardant properties of the SR composite.