The invention discloses an ethylene-propylene-diene monomer rubber used for manufacturing a wind energy cable and a preparation method thereof. The ethylene-propylene-diene monomer rubber comprises the following components: 90-110 parts of ethylene-propylene-diene monomer rubber, 1-4 parts of anti-aging agent, 0.2-0.5 part of stearic acid, 2-9 parts of paraffin oil, 2-5 parts of lead sulfate tribasic, 1-4 parts of zinc oxide, 80-120 parts of activated kaolin, 0.3-1.5 parts of coupling agent, 0.5-2.6 parts of cross-linking agent, 0.5-2.0 parts of assistant crosslinker, 1-3 parts of semi-reinforcing carbon black, 1-4 parts of plasticizer, 0.5-2 parts of antimonous oxide, 0.5-2 parts of zinc borate, 1-5 parts of basic magnesium carbonate, 1-4 parts of antioxygen, 0.1-0.5 part of sulphur, 2-5parts of epoxidized soybean oil, 5-15 parts of decabromodiphenyl ether, 12-30 parts of antimony oxide and 2-5 parts of organic modified bentonite. The material has the advantages of wide applicable temperature range, god performance and long service life.