In application to a superconducting magnet which is cooled by a cryogenic refrigerator, provided is a superconducting coil which can maintain a cooled state and enables a stable operation and continuous driving even if a ramping speed is increased. First and second superconducting conductors are connected with each other. Respective tape-like superconducting multifilamentary wires are electrically connected with each other through solder, to form joint bodies. The respective joint bodies are insulated from each other by interposition of an insulating material therebetween.