A heat-resistnat wire is disclosed which comprises a line of copper or aluminum coated with a shielding material obtained by heating a mixture of: (A) an ethylenic copolymer comprised of ethylene and 0.1 to 20.0 mol % of a monomer of at most 30 carbon atoms having an oxirane group or a hydroxyl group and having at least one double bond; and (B) an ethylenic copolymer comprised of ethylene and 0.1 to 20.0 mol % of a monomer possessing a functional group capable of reacting with oxirane group or hydroxy group in the ethylenic copolymer (A). The wire is excellent not only in heat resistance but also in insulating ability and flexibility.
