A grain sorter is provided to efficiently sort grains through the sorting holes by moving predetermined quantities of grains through openings between partitions and sorting porous bodies, thereby uniformly distributing the grains onto inner surfaces of the sorting porous bodies without applying a load to the sorting holes. A grain sorter comprises: a sorting part(2) including sorting porous bodies(21) having a plurality of sorting holes(211) formed therein to sort inferior bean and good bean from grains injected through an injection hopper(11), and partitions(212) installed inside the sorting porous bodies and spaced from the inner sides of the sorting porous bodies in a predetermined distance; and a drive part(3) rotating the sorting part. The sorting part comprises: a porous body brush roll brought into contact with outer peripheral surfaces of the sorting porous bodies to prevent large quantities of grains, inferior bean and foreign materials injected into the sorting porous bodies from being jammed into the sorting holes; and an interior bean-housing hopper(23) including an inferior bean outlet(231) discharging the large quantities of grains and foreign materials injected into the sorting porous bodies and an inferior bean brush(232) transferring the large quantities of grains and foreign materials to the inferior bean outlet.
