Abstract: The effect of vacuum ultraviolet (VUV) irradiation on the surface morphology, mass loss, thermal properties and optical property of the additional silicone rubber reinforced with MQ resin was studied by space combined radiation simulator. The results showed that the aging crackle was produced on the surface of rubber after irradiation and the quantity of the crackle increased with the increase of irradiation dose. There was mass loss of the silicone rubber after VUV irradiation and the mass loss percentage increased with the increase of irradiation dose. The thermostability of the silicone rubber increased firstly and then decreased with the increase of irradiation dose. The VUV irradiation had little effect on the body inflation/shrinkage distortion of the silicone rubber, but it had sign