The analysis of resource-saving technologies of cultivation and refinement of agricultural crops confirmed that the use of PSS pneumatic sorting tables allows to somewhat reduce the costs of cleaning and sorting. However, the imperfection of their designs and uneven grain supply reduces the effectiveness of their use. Therefore, the purpose of the research was to improve the quality of post-harvest processing of grain crops, the development of a rotary feeder. To achieve this goal, research methods and techniques have been developed. A pneumatic sorting table equipped with a three-blade rotary feeder with an outer diameter of 80 mm with straight blades located at an angle of 120 degrees has been developed. The process of grain flow motion in the hopper was studied and dependencies were established to determine grain motion in the hopper, the time of grain motion in the area under consideration and the speed of grain motion at the exit from the hopper, which was 1.167 m/s. The equations of motion of the blades for the outer and inner diameter of the rotary feeder are established, according to which the actual coordinates of their motion and displacement of the shaft axis of the rotary feeder from its original position are calculated. Calculations have determined that with an outer diameter of 0.08 m of the rotary feeder, grain velocity of 1.02 m/s, an angular velocity of 2.9 s-1, the displacement of the shaft axis of the rotary feeder from its original position at a 360 degree rotation angle will be 160 mm. This will reduce the unevenness of grain supply, and grain shattering, increase laboratory and field germination, improve the content of the output groups of full-fledged grain and, consequently, improve the quality of post-harvest processing of grain crops by a developed pneumatic sorting table equipped with a three-blade rotary feeder.