<p>An electric supercharger comprises a turbine shaft (12) having a turbine impeller (11) at its one end; a compressor impeller (14) rotatingly driven by the turbine shaft; a housing surrounding the turbine impeller, the turbine shaft and the compressor impeller; a motor stator (24) fixed in the housing; and a motor rotor (22) rotatingly driven by the motor stator. The motor rotor (22) is fixed to the inner diameter side of the compressor impeller (14) by interference fitting.</p>
