[Objective] The research aimed to provide the guidance for the production of polysaccharide from the crown of sweet potato and the comprehensive utilization of sweet potato.[Method] With Yushu 10 as tested material,4 pretreatment methods including blanching fresh samples,the fresh-keeping storage of fresh samples,natural withering of fresh samples,drying the fresh samples to study the effects of using different pretreatment methods in the crown of sweet potato after collection on its polysaccharide content....