Potato starch has better characteristic and unique use. It’s granular diameter is big and range is wide. Paste melting temperature is low and swelling power is easy for potato starch.Its keeping water power was strong, when starch granular paste was melting. Good maximum viscosity and transparency has an unique effect on processing flour, aquatic livestock, small cake, granular power, denatured starch. Starch molecule of potato has phosphoric acid-group, phosphorus content has big effect on character of potato starch, and phosphorus different content of potato starch has difference in its usage. Genetic improvement is effective means for gaining processed materials of phosphorus different content; culture technique and other management measure could regulate phosphorus content of processed materials variety. Big starch granular could perform character of potato starch perfectly, when different granular diameter was graded.