The invention discloses high-temperature vulcanized silicone rubber for a cold-contracted sleeve and a process for the high-temperature vulcanized silicone rubber. The silicone rubber is prepared from the following raw materials in parts by mass: 12 to 20 parts of first silicone raw rubber, 15 to 23 parts of second silicone raw rubber, 47 to 66 parts of third silicone raw rubber, 8 to 20 parts of fourth silicone raw rubber, 1 to 8 parts of fifth silicone raw rubber, 0 to 3 parts of vinyl silicone oil, 0 to 5 parts of dimethylsilicone oil, 28 to 40 parts of white carbon black, 2 to 8 parts of silazane, 1 to 4 parts of de-ionized water, 1.2 to 5 parts of a silane coupling agent and 0.08 to 0.3 part of an internal releasing agent, wherein the first silicone raw rubber and the second silicone raw rubber are methyl-terminated methylvinyl silicone raw rubber with different vinyl molar contents; the third silicone raw rubber, the fourth silicone raw rubber and the fifth silicone raw rubber are vinyl-terminated methylvinyl silicone raw rubber with different vinyl molar contents. The cold-contracted sleeve made from the silicone rubber is strong in tear strength and stretching tensile strength, high in breakage elongation and low in stretching permanent deformation rate.