Efficient ventilation device

An efficient ventilation device is characterized by adopting a fan to enable a ventilation wind field to ventilate. A one-way guide body is arranged at a wind outlet of the fan, the one-way guide body is in a shape of a taper, the small end of the taper right faces to a fan blade of the fan, flowing directions of the wind are changed by the one-way guide body, the one-way guide body can be of a solid structure, a taper with holes on the middle portion or a hollow taper, and the taper of the one-way guide body is one of a liner taper, a convex curve taper or a concave curve taper. The efficient ventilation device has the advantages of reducing turbulent flow and wind drag, enabling wind of the fan to be smoothly led out, enabling the wind to be evenly sent to the ventilation wind field and accordingly increasing ventilation performance.