An easy-to-maintain polishing roll is provided. A grain feeding roll for feeding grain and a polishing roll having air jet openings and agitator protrusions on the outer peripheral part thereof have amain shaft passing therethrough. The polishing roll is constituted of a plurality of divided roll parts obtained by dividing the polishing roll into multiple parts in the axial direction. The polishing roll has support members for joining the divided roll parts to each other in the axial direction and fixing the divided roll parts on the main shaft.