The paper analyzes the existing theoretical research of corn seed separation and calibration processes. The machines, tools and equipment that implement the process were studied. An innovative sieve with openings in the Cassini oval shape was proposed for the economical separation and calibration of corn seeds. The results of operation of the proposed sieve in the operating conditions of Kharkiv Feed Mill on BSH-100 serial separators were considered. The study of the effectiveness of sifting corn seeds through the holes of the sieves was carried out in partnership with the State University “Ukrainian Research Institute of Forecasting and Testing of Agricultural Production Techniques and Technologies named after Leonid Pohorily” (Kharkiv Branch). The use of sieves with openings in the Cassini oval shape, instead of classic circular base openings, was found to result in an increase in throughput capacity of the sieve and open area of up to 20%.