A motor assembly includes a motor, a housing that houses the motor, an inverter that is electrically connected to the motor, an inverter case that houses the inverter and is provided integrally with the housing, a wire harness electrically connected between a connector of the inverter case and a connector of the housing, a cooling water hose connecting between a hose nipple of the inverter case and a hose nipple of the housing, and a retainer to fix the wire harness and the cooling water hose in a bundled state to the housing. The housing includes an axle connecting portion to which an axle of a vehicle is connected, and the wire harness is farther away from the axle than the cooling water hose at a position facing the axle.