An in-wheel motor drive device comprising: an electric motor configured to drive a wheel, the electric motor including a motor stator fixed to a motor housing; a wheel bearing configured to rotatably support the wheel; a speed reducer configured to transmit rotation with a speed that is reduced with respect to that of rotation of the electric motor to the wheel bearing; a lubricating oil supply mechanism (Jk) including a lubricating oil passage formed inside a speed reducer housing of the speed reducer, and a supply oil passage configured to supply a lubricating oil from the lubricating oil passage to the electric motor, the lubricating oil passage including a lubricating oil tank, the lubricating oil tank being positioned at a lower portion of the reducer housing to store the lubricating oil and being in communication with a lower space inside the motor housing, characterized in that the lubricating oil supply mechanism (Jk) including a pump configured to supply the lubricating oil from the lubricating oil passage to the electric motor through the supply oil passage, the pump being disposed between the electric motor and the speed reducer so as to be concentric with the electric motor and the speed reducer; an oil temperature sensor (Sb) disposed in the lubricating oil tank in the speed reducer to measure a temperature of the lubricating oil in the lubricating oil tank; a coil temperature sensor (Sa) disposed on the stator of the electric motor to measure a temperature of a motor coil; and a controller configured to control the electric motor, and including a motor output limiting module configured to limit an electric current in the electric motor when at least one of the temperature measured by the oil temperature sensor (Sb) and the temperature measured by the coil temperature sensor (Sa) has exceeded a corresponding predefined threshold value. an electric motor configured to drive a wheel, the electric motor including a motor stator fixed to a motor housing; a wheel bearing configured to rotatably support the wheel; a speed reducer configured to transmit rotation with a speed that is reduced with respect to that of rotation of the electric motor to the wheel bearing; a lubricating oil supply mechanism (Jk) including a lubricating oil passage formed inside a speed reducer housing of the speed reducer, and a supply oil passage configured to supply a lubricating oil from the lubricating oil passage to the electric motor, the lubricating oil passage including a lubricating oil tank, the lubricating oil tank being positioned at a lower portion of the reducer housing to store the lubricating oil and being in communication with a lower space inside the motor housing, characterized in that the lubricating oil supply mechanism (Jk) including a pump configured to supply the lubricating oil from the lubricating oil passage to the electric motor through the supply oil passage, the pump being disposed between the electric motor and the speed reducer so as to be concentric with the electric motor and the speed reducer; an oil temperature sensor (Sb) disposed in the lubricating oil tank in the speed reducer to measure a temperature of the lubricating oil in the lubricating oil tank; a coil temperature sensor (Sa) disposed on the stator of the electric motor to measure a temperature of a motor coil; and a controller configured to control the electric motor, and including a motor output limiting module configured to limit an electric current in the electric motor when at least one of the temperature measured by the oil temperature sensor (Sb) and the temperature measured by the coil temperature sensor (Sa) has exceeded a corresponding predefined threshold value.