A superconducting cable line includes a heat insulation pipe for a fluid for transporting liquid hydrogen, a superconducting cable housed in the heat insulation pipe for a fluid, and heat exchange means for performing a heat exchange between liquid hydrogen and a refrigerant of the cable. The superconducting cable includes a cable core inside a heat insulation pipe for a cable and is housed in the heat insulation pipe for a fluid to form a low temperature environment around the cable and a double heat insulation structure including the heat insulation pipe. Therefore, since heat intrusion into the superconducting cable is reduced and the refrigerant is cooled with liquid hydrogen, the line can reduce energy for cooling the refrigerant.