The invention discloses a heat conductive cable material which comprises, by weight, 100-120 parts of modified ethylene-propylene-diene monomer rubber, 10-30 parts of talcum powder, 20-50 parts of carbon black, 1-3 parts of epoxidized soybean oil, 20-30 parts of magnesium hydrate, 10-20 parts of micro-capsulated red phosphorus, 5-10 parts of expansible graphite, 1-2 parts of sulphur, 0.1-0.3 part of zinc oxide, 0.2-0.4 part of stearic acid, 0.2-0.4 part of accelerant M, 4-6 part of Ca / Zn composite stabilizer and 2-4 parts of montan wax. In the preparation process of the modified ethylene-propylene-diene monomer rubber, phenolic resin is added into ethyl alcohol to be dissolved, silane coupling agent modified carbon nanotubes are added, stirring is carried out, rotary evaporation is carried out to remove ethyl alcohol, and drying is carried out to obtain a material A; the material A and ethylene-propylene-diene monomer rubber are mixed to be uniform, the temperature is increased, heat insulation and stirring are carried out, and the modified ethylene-propylene-diene monomer rubber is obtained. The heat conductive cable material is good in heat conductivity and high in mechanical performance.