The invention relates to a cable core body. The cable core body comprises a conductor made of an aluminum alloy material, wherein the aluminum alloy material is prepared from the following components in percentage by weight: 1.1 to 8.3 percent of carbon nanotube, 0.15 to 0.43 percent of manganese, 0.14 to 0.33 percent of silicon, 0.16 to 0.23 percent of iron, 0.08 to 0.18 percent of gallium, 0.02 to 0.05 percent of mixed rare earth element, 0.02 to 0.04 percent of tin, 0.02 to 0.035 percent of magnesium, 0.02 to 0.16 percent of germanium, 0.01 to 0.13 percent of titanium, 0.01 to 0.11 percent of chromium, 0.01 to 0.08 percent of nickel, 0.01 to 0.06 percent of copper, and the balance of aluminum and inevitable impurities; the mixed rare earth element is prepared from the following components in parts by weight: 22 to 31 parts of lanthanum, 18 to 23 parts of ytterbium, 11 to 26 parts of promethium, 9 to 17 parts of terbium, 7 to 13 parts of neodymium, 5 to 10 parts of europium and 3 to 6 parts of scandium. According to the cable core body disclosed by the invention, by improving an aluminum alloy formula, resistance of the cable core body is reduced, electrical conductivity is improved and energy consumption during power transmission is reduced; meanwhile, tensile strength of the cable core body is improved, and industrial practicality of the cable core body is improved.