The invention discloses a sorting device for a coarse coal slime interference bed based on gravity and interfacial force, a method and application thereof, wherein air bubbles are introduced into the sorting device of the interference bed. Under the action of ascending water flow, an environment similar to heavy medium sorting is formed by using fluidization of fine coal slime carried in fed materials; and the introduced air bubbles are attached to hydrophobic low density particles so that the real density of an air bubble-hydrophobic particle polymer is reduced and the density difference between head coals and minerals is increased. The sorting device realizes the sorting based on the combined action of gravity and interfacial force in a solid-liquid-gas three-phase interference bed, has large adaptation range to the particle size of the fed materials and high sorting precision, can effectively sort coarse coal slime which has wide level and is difficult to sort, and is in particular applicable to the sorting of the coarse slime of which the particle diameter is between 2 and 0.3 millimeter.