Seed classification choose test bench mainly take advantage of small differences in grain dimensions after cleaning the seeds of the grading. Upper and lower sieve tube are cylindrical structure, the sieve of hole, the classification for seed width; sieve for the long hole for the seed thickness grading. Over-filled hopper with the same structure and dimensions of the bottomless funnel, can be exchanged according to the graded requirements of the seed . Vibrating conveyor system were installed in the upper and lower sieve tube below the grade (through sieve) after the seeds were transported to the hopper filled. The electromagnetic vibration feeder feed rate, screen cylinder speed are adjustable to meet different shapes, different dimensions seed grading requirements, obtain the batch seed.