To inhibit occurrence of oil coking in a compressor housing even if the trend of high supercharging progresses, accompanying the trend of high output of engines, in an internal combustion engine with a supercharger.

Intake air is forcibly fed in a combustion chamber 2a of the engine 2 with a compressor wheel 52 receiving torque of a turbine wheel 51 in a compressor housing 30 provided in an intake passage 3 of the engine 2. Since an oil reservoir part 100 is formed on an inner surface of the compressor housing 30, oil contained in intake air is accumulated in the oil reservoir part 100 by centrifugal force generated by rotation of the compressor wheel 52.