To obtain a rotor of a superconducting generator which can sufficiently absorb the thermal contraction difference between a field winding attachment shaft and an ordinary temperature damper, can also sufficiently absorb the centrifugal expansion difference between them, and can reduce a stress applied to a flexible disc.

A flexible disc 10, whose one end is fixed to a field winding attachment shaft 3 and whose other end is fixed to an ordinary temperature damper, is deformed into a bent shape.