Due to a centrifugal force in a vehicle width direction due to turning of an automobile, oil in an electric motor housing chamber housing an electric motor and oil in a transmission housing chamber housing a reduction gear and a differential gear flows to-and-fro via oil communication passages that penetrate a partitioning wall. An opening on the transmission housing chamber side of the oil communication passages is spaced from the partitioning wall. Hence, when oil moves from the transmission housing chamber side to the electric motor housing chamber side, it is possible to prevent the oil quantity on the electric motor housing chamber side from increasing excessively and suppress an increase in resistance to oil stirring by a rotor of the electric motor while retaining a constant oil amount on the transmission housing chamber side to ensure lubricating performance for the reduction gear and the differential gear.