PURPOSE: To reduce the operating cost and improve the thermostability by connecting the connection end section of a superconductive wire with a ceramic superconductor made of Ba-La-Cu-O, La-Sr-Cu-O, La-Ca-Cu-O, Y-Ba-Cu-O, Yb- Ba-Cu-O, Sc-Ba-Cu-O or the like.

CONSTITUTION: The connection section of a superconductive wire or a superconductor is connected with a ceramic superconductor. Ba-La-Cu-O, La-Sr-Cu-O, La-Ca-Cu-O, Y-Ba-Cu-O, Yb-Ba-Cu-O, Sc-Ba-Cu-O or the like are used for the ceramic superconductor. The connection end section is formed into a taper shape, or the end section is cut off perpendicularly to the axis, and the cut face is smoothed and cleaned.