To decrease an outside volume and efficiently perform the lubrication and cooling of bearings by eliminating a filling tube for returning a pumped fluid to a main flow passage in a motor pump allowing the pumped fluid to invade into a motor such as a geared motor pump.

A pump casing 16 storing the centrifugal pump 12 and a motor casing 18 storing the canned motor 14 are integrally connected to each other. The pumped fluid discharged from the centrifugal pump 12 flows through the main flow passage 40 between an inner case 20 storing a stator 28 and the motor casing 18. The fluid flowing in a can 24 storing the rotor 22 is converged in the pump casing. An auxiliary impeller 44 is disposed near the rear bearing 38 supporting a shaft 32 to form a flow in the can.