Abstract: A motor-pump unit consists of a screw shaft pump and a slot-barrel motor located on the pressure side of the pump. The motor-pump unit is provided with a rigid, preferably one-piece, shaft by which the motor drives the pump. The motor is located on the pressure chamber of the pump with a bearing between the motor and pump. The shaft is supported within the pump, in part by the bearing, and the rotor of the motor is cantilevered on the free end of the shaft outside the pressure chamber. The pot-shaped stator part of the motor is telescoped over the rotor and fastened directly to the pressure side of the pump.