A supercharger apparatus is provided which comprises a reciprocating type internal combustion engine having a block, an exhaust passage and an intake passage, and also having an exhaust turbine which is provided in said exhaust passage. A compressor is provided in said intake passage, along with a shaft for interconnecting said turbine and said compressor, the shaft being supported in a bearing hole which is formed in the engine block. A lubrication oil passage, which is in communication with the bearing hole, is formed in the engine block.