To provide a device for performing hydraulic power generation without being constructed to improve power generating efficiency with a hydraulic water stream resulting from deep draft, and for performing water quality purification while solving an inconvenience that fluid agitating effects due to the water stream are not improved.

The underwater self-sinking of the device brings about deep draft, and hydraulic fluid energy from pressure generated in an object by water is given to a turbine with synergetic effects by high pressure direct injection and the rotating force of a spiral blade so that a generator generates power through a reduction gear. A hydraulic water stream circulating between the device and its outside brings agitating effects in a water surface area, and a water quality purifying water turbine is operated in an underwater area by underwater lifting power, thus improving a water quality purifying function.