Purple sweet potato grain powder formed after dewatering the sweet potato tuber, to disperse single cell, the cell wall of this kind of product is unbroken, and the substance within cell didn't lose, so it remains its original nutrition and flavor. For its low cell wall broken rate, its physical characteristics have improved, it has got good commodity. It has many characteristics, such as low viscosity, balanced water-absorbability, it can be made into bread, steam bread, puff food and soup, etc.