PURPOSE: To provide a ceramic superconductor suitable for a conductor of a cable for transporting electric power, having a small diameter, excellent in flexibility and superconductivity.

CONSTITUTION: A plurality of ceramic superconductive wire rods 1 each having a sectorial cross section are spirally wound around a pipe (former) 2 having a circular cross section singly or with reinforcing wire rods 7 having the same shape, which are replaced with some of the wire rods 1, in contact with each other, thus forming a superconductor layer 8. Since the ceramic superconductive wire 1 and the reinforcing wire 7 to be wound around the former 2 are formed in sectorial cross section, they can easily be wound in alignment in high density on the former 2. Consequently, it is possible to reduce a diameter, prevent a damage on the ceramic superconductive wire 1 during the winding work, and achieve excellent flexibility and superconductivity.