This double layer cereal destoner may be used to continuously remove stones from creal such as yellow rice, maize, bean, bareley, highland bareley, soybean and etc. People can separate them easily and reliably through the difference between grain and heavy impurities (e.g. gravel, metal, glass, etc.) on specific gravity and suspension speed. Stoning efficiency is high; grains contained in graves are very few; the structure of this cereal destoner is compact and the tightness is good; there is no dust inside out; the operation is easy and simple; there is meter showing negative pressure; care and maintenance is simple and energy consumption is low; it is equipped with automatic material control component and adopts electronic sensor to achieve automatic feed and machine halt and starting up.