The invention provides a biomass particle sorting device. The biomass particle sorting device comprises bearing tiles, tooth grooves, separation tiles, a scraping rod, a biomass particle containing box, a selecting column, a rotating shaft, a selecting block, a base, rotating rollers, tooth convex, an abutting plate, connecting blocks and connecting grooves, wherein the connecting grooves are formed in the centers of the bottom surfaces of the bearing tiles, the separating tiles are movably arranged at the tops of the bearing tiles, the biomass particle containing box is arranged on one side of the bearing tiles, the scraping rod is fixedly arranged on one side, close to the separating tile, of the biomass particle containing box, the selecting column is fixedly arranged on one side, awayfrom the biomass particle containing box, of the bearing tiles, the rotating shaft is arranged on one side, close to the bearing tiles, of the selecting column, the surface of the rotating shaft is welded to the selecting block, a part of biomass particles can be taken away from the biomass particle containing box through the bearing tiles, the other end of the biomass particle is attached to theabutting plate at the other end of the inclined bearing tiles and the separating tiles, so that the biomass particles can be automatically exposed on the outer side of the bearing tiles according to the length of the biomass particle, so that later-stage selection is facilitated.