The invention discloses a heatproof high-strength cable which comprises a conductor, an insulating layer, a high-temperature-resistant layer and an outer sheath insulating layer which are made of a modified polyvinyl chloride material. The modified polyvinyl chloride material comprises polyvinyl chloride, nylon, maleic anhydride grafted polyphenyl ether, bisphenol-A polycarbonate, stearic acid pentaerythritol ester, trioctyl trimellitate, stearic acid, isopropyl phenyl diphenyl phosphate, calcined kaolin, modified nano-calcium carbonate, maleic acid modified hydrotalcite, modified graphene oxide, carbon nanofibers, diethyl dithiocarbamate neodymium, calcium adipate, glyzinc, beta-diketone, pentaerythritol, ethylene-vinyl alcohol and antioxidant. The heatproof high-strength cable is high in intensity, good in heat resistance and long in service life.