The invention relates to a cable jacket rubber and a preparation method, wherein the cable jacket rubber has high elastic resilience, softness and abrasive resistance at a low temperature. The cable jacket rubber is characterized in that a base material of the rubber is formed by mixing 30 to 50 weight percent of natural gum and 50 to 70 weight percent of cis-butadiene rubber; a vulcanizing systemin a rubber compounding agent is a low-sulfur high-accelerant vulcanizing system, the addition of sulfur is 0.3 to 0.6 weight percent of that of the base material of the rubbere, the addition of theaccelerant tetramethylthiuram disulfide is between 1.0 and 1.3 weight percent, the addition of the accelerant N-cyclohexyl-2-benzothiazole sulfonamide is between 1.8 and 2.2 weight percent, and the addition of the accelerant diphenyl disulfide benzothiazole is between 0.6 and 0.9 weight percent. The cable jacket rubber has wide range of working temperature, and can be bent and distorted randomly without cracking at a long-term usage temperature of between 50 DEG C below zero and 70 DEG C, the impact elasticity is high and can reach 42 percent, the specific elongation is more than 350 percent,and the Akron abrasion loss is less than 2 percent, thus the cable jacket rubber is particularly suitable for wind-power generated electricity tower tube cables.