A housing of a compressor supports a rotary shaft. The rotary shaft is coupled to a pulley with a pulley one-way clutch and is coupled to a rotor of an electric motor with a motor one-way clutch. The pulley is supported by the housing with a pulley bearing. The electric motor overlaps a power transmission portion in the axial direction of the rotary shaft. At least two of the bearing, the pulley one-way clutch, the motor one-way clutch, and a brush device of the electric motor overlap each other in the axial direction of the rotary shaft. As a result, the size of the compressor is reduced in the axial direction of the rotary shaft.