PURPOSE: To ensure that the supply of cereal grains to a multi-stage shaking separator plate and a production system are rationalized.

CONSTITUTION: The subject cereal grain allotment device consists of vertical supply aperture groups provided on the rock-up side end or the shake-down side end of a shaking separator plate, allotment flow paths 36, 36... in an allotment case for cereal grains from an allotment trough 17, and a projecting allotment case 18b which juts out an allotment flow path 36 as a part of the allotment case to a vertical outside area from the supply side end of the shaking separator plate, in the supply route to each shaking separator plate through the supply aperture group. Further, an opening to the horizontal rock-down side of the shaking separator plate in the projecting allotment case 18b closed by a closing plate formed in a folded manner and in one complete piece with a side wall on the supply of the shaking separator.