According to the present invention, there is provided a turbocharger that can endure high-speed rotation and can be manufactured with high productivity.
The turbocharger including a turbine wheel (20), a compressor wheel (40)and a rotor shaft (10) that couples the turbine wheel and the compressor wheel and is rotatably supported in a bearing housing, which is characterized in that a joint collar (30) having a groove portion on an outer periphery surface thereof, is interposed between the rotor shaft and the turbine wheel and couples the rotor shaft and the turbine wheel, the rotor shaft is made of a material having high rigidity, and the joint collar is made of a material having rigidity lower than that of the rotor shaft.