A motor includes a rotor having a permanent magnet fitted thereon, and a stator having an inner peripheral surface spaced a predetermined distance from an outer peripheral surface of the rotor in opposed relation thereto, and the stator is press-fitted in a motor case to be fixed thereto with its outer peripheral surface. A plurality of projecting portions are formed on an inner peripheral surface of the motor case. Recess portions for engagement with the respective projecting portions are formed in the outer peripheral surface of the stator. When the stator is press-fitted into the motor case, the stator is fixed to the motor case with inner bottom surfaces of the recess portions serving as press-fitting surfaces. The projecting portions of the motor case are engaged respectively in the recess portions of the stator, thereby preventing the rotation of the stator relative to the motor case.