Rice screening device capable of conveniently adjusting screening size

The utility model relates to the technical field of rice screening, and provides a rice screening device capable of conveniently adjusting the screening size, which comprises a main box body, three support plates are arranged in the main box body at equal intervals, and support rods are fixedly arranged between one side of each support plate and one side of the inner wall of the main box body; fixing blocks are slidably connected to the outer sides of the supporting rods, a first spring is arranged on the outer side of each supporting rod and located between one fixing block and the supporting plate in a sleeving mode, screening boxes are fixedly installed among the four corresponding fixing blocks, and first sliding grooves are formed in the outer sides of the bottoms of the screening boxes; second sliding grooves are formed in the positions, located below the first sliding grooves, of one side of the inner wall of the screening box correspondingly, and pressing plates are slidably connected into the first s