Seed screening machine take advantage of differences in width or thickness of seed for seed screening test or a small amount of seed grading. This machine use seed size, shape characteristics to separate seed raw materials into the biggest grain, the second largest grain, good seeds and small miscellaneous other four parts, to facilitate the use of length or gravity separation equipment to seed a complete separation.Screening for the seed box wooden structure, the internal installation of three sieve; reciprocating motion passed by the drive to achieve different seed size grading and screening tests, to obtain the width of the batch of seed size distribution of the proportion, screening for the development of seed selection and wind provide the basic data processing equipment.