An electric motor structure includes a rotary shaft with a coolant passageway therein and a rotor with a cooling surface non-rotatably coupled to the rotary shaft. The coolant is supplied from the coolant passageway of the rotary shaft to the cooling surface of the rotor and flows along the cooling surface of the rotor as a liquid film. The electric motor structure is further provided with a coolant discharge restricting section configured and arranged to restrict discharging of the coolant from the cooling surface. The coolant discharge restricting section protrudes from the cooling surface in a direction substantially perpendicular to the cooling surface where the coolant flown along the cooling surface is discharged from the cooling surface. Thus, a high cooling performance is obtained even when the rotor rotates at high rotational speeds by maintaining a sufficient liquid film thickness.