Abstract: A seed sorting machine contains a feeding area, a plurality of filtration units, a classification assembly, multiple guiding assemblies, a delivery unit, and at least one pressing rod. Each filtration unit includes multiple holding trays, a plurality of first partitions, and each holding tray has a filtering hole. The classification assembly includes a classifying tray, multiple guide sheets, and a plurality of outlets. Each guiding assembly includes a holder and multiple ribs, wherein between any two adjacent of the multiple ribs is defined a slot which corresponds to each of the plurality of outlets. The delivery unit includes a base on which multiple V-shaped grooves and multiple second partitions are arranged. Each pressing rod includes a plurality of rollers and multiple trenches, wherein each of the multiple trenches is defined between any two adjacent of the multiple trenches and corresponds to each of the multiple V-shaped grooves.