The invention relates to a dust extraction device, specifically a horizontal full-section efficient dust extraction device for coal mine. The horizontal full-section efficient dust extraction device for coal mine comprises two grades of special-shaped horizontal demist devices, that is, the coarse grade special-shaped horizontal demist device and the fine grade special-shaped horizontal demist device respectively; each grade of special-shaped horizontal demist device comprise a plurality of sets of special shaped dust extraction blades installed abreast; the front end and the rear end of the coarse grade special-shaped horizontal demist device are provided with full section mist sprayers correspondently; the rear end of the fine grade special-shaped horizontal demist device is provided with a full section mist sprayer; and the lateral side of each grade of special-shaped horizontal demist device is provided with a catchment groove. According to the dust extraction device with high efficiency for a coal mine horizontal full section provided by the invention, dust extraction efficiency is improved substantially; the dust extraction efficiency of total dust in a roadway is improved from full section mist spray 23% to full section mist spray 55%; the dust extraction efficiency of respirable dust is improved from full section mist spray 20% to full section mist spray 60%; the dust extraction efficiency of total dust in the roadway and the dust extraction efficiency of respirable dust are improved by 140% and 200% correspondingly; full section dust extraction is achieved without a dead corner; the stability of the mist spraying device is improved; the structure is stable; and collapse is not liable to happen.