Abstract: The methods of extraction,purification and anticoagulant activities of polysaccharides were researched from sweet corncob. The polysaccharides were extracted with the method of water,the removing protein of polysaccharides with the methods of trichloroacetic acid,enzyme and Sevag-enzyme respectively. The decoloration of polysaccharides by hydrogen peroxide and resin,anticoagulant activities of polysaccharides were researched after grading use alcohol. The results showed that the optimum yield of polysaccharides was up to16.7% with the method of water.The deproteinization effect of sevag-enzyme was best,the removal rate of protein and the recovery rate of polysaccharides of sweet corn cobs was 84.94% and 70.74%,respectively. The decolorization effect of D301 R resin was best,the decolorization rate and the recovery rate of polysaccharides of sweet corn cobs was 46.17% and 99.23%,respectively. Anticoagulant activities in vivo and vitro showed that polysaccharides and different fractions of sweet corncobs had a significant influence on bleeding time and blood coagulation time( p < 0.05),all the components can prolong APTT and TT( p < 0.05),but had no significant effect on PT( p > 0.05),the anticoagulant activities of SCP-80 was better.