The invention discloses a device for efficiently purifying eutrophic water. The device comprises a suspension frame, a suspension barrel, a dialysis space ring, an inner barrel, a water pump, a water draining pipe, a filler and an aerating device, wherein the suspension frame which is coincided with the axis of the suspension barrel is arranged on the upper part of the suspension barrel; the dialysis space ring is coaxially arranged in the suspension barrel so as to divide the suspension barrel into a purifying filtering barrel and an inner barrel, wherein a water feeding hole is formed in the suspension barrel wall of the purifying filtering barrel; the purifying filtering barrel is filled with the filler; the water pump is arranged in the inner barrel, and is connected with the outside through the water draining pipe; the aerating device is arranged at the top of the suspension frame and is connected with the purifying filtering barrel through an air pipe. According to the device, the filler adsorbing culturing microorganism is arranged in the purifying filtering barrel and the microorganism is utilized to degrade and purify the pollutants in water, so that the purposes of gradually purifying water and recovering excellent aquatic ecological environment of water are achieved, the anti-pollution impact capacity of water is enhanced, the water eutrophication is effectively controlled and the original ecological recovering and self-cleaning of water are realized.