Seed grading and screening device

The utility model discloses a seed grading and screening device which comprises a frame body. A first air blowing mechanism is arranged on one side of the upper portion of the containing cavity of the frame body, a chipping guiding part is arranged on the other side opposite to the first air blowing mechanism, a downward discharging channel is arranged between the end, facing the first air blowing mechanism, of the chipping guiding part and the first air blowing mechanism, and a first chipping discharging port penetrating through the frame body is formed in the other end of the chipping guiding part. A screen drum is arranged below the scrap guide part; a receiving hopper corresponding to the blanking channel is arranged on the screen drum; the screen drum comprises multiple stages of grading screening areas, a material receiving barrel is arranged corresponding to each stage of grading screening area, and the bottom end of each material receiving barrel is fixedly connected with an air blowing discharging ba