An integrated drive motor unit which is integrally constituted of a motor, an inverter and a reducer differential unit arranged in a row, and a frame member. The reducer differential unit is connected to an output shaft of the motor, and distributes torque of the motor to a pair of axles, one of which passes through the inverter. The frame member constitutes a part of the motor and a part of the reducer differential unit, and has a portion surrounding the axle passing through the inverter. The inverter is disposed outside the frame member.