A supercharger includes a turbine housing, a waste gate valve, a supporting member. The turbine housing includes a bypass passage allowing exhaust gas to flow by bypassing a turbine wheel. The waste gate valve includes a valve and a spindle, the valve is configured to close the bypass passage, the spindle being connected to the valve, and the waste gate valve being configured to oscillate the valve by allowing the spindle to pivot and control a flow rate of the exhaust gas passing through the bypass passage. The supporting member fixed to the turbine housing to pivotably support the spindle. The supporting member being formed of a material higher in rigidity than a material constituting the turbine housing, and the supporting member abutting against a first exhaust system member connected to an exhaust downstream side of the turbine housing.