Abstract: An object of the present invention is to achieve more high-speed rotation of a rotor to which a test object is stored, extending the duration of high-speed rotation, and temperature control of a rotor at the time of high-speed rotation. A high-speed rotation testing apparatus of the present invention comprises: a rotor having a hollow for a test object, to which a predetermined test object is stored; a spindle connected to the rotor; a torque applying device for applying a predetermined torque to the spindle, and a casing for sealing the rotor. The casing comprises a decompressing device and a holder for holding the spindle. The holder has a bushing for supporting the spindle and a bushing supporting member for supporting the bushing by inserting thereto. By forming the inner diameter of at least one of the bushing supporting member larger than the outer diameter of the bushing, the bushing supporting member supports the bushing to be rotatable.