An inner peripheral edge of a first annular member includes a plurality of first inner edge portions belonging to an angular range in which support holes exist in the circumferential direction of a turbine rotor and a plurality of second inner edge portions belonging to an angular range in which the support holes do not exist in the circumferential direction of the turbine rotor. At least one second inner edge portion of the plurality of second inner edge portions comprises a recess portion recessed outward in a radial direction of the turbine rotor, the recess portion extending in an axial direction of the turbine rotor from the side of exhaust gas.