Abstract: L135,Xiang 66,808,Rida four strains of Lentinus edodes were used as the research objects.The contents of extracellular polysaccharides were determined by phenol-concentrated sulfuric acid method, the inhibition of bacteria was studied by filter paper diffusion method, and the antioxidant activity of polysaccharides in vitro was investigated by spectrophotometer, in order to provide reference for the development of Lentinus edodes medicinal and food resources.The results showed that the extracellular polysaccharide contents of Lentinus edodes L135,Xiang 66,808 and Rida were（2.82±0.02）mg·mL^-1,（1.85±0.03）mg·mL^-1,（1.61±0.04）mg·mL^-1 and（2.22±0.06）mg·mL^-1.When the concentration of Xiang 66 reached 1.0 mg·mL^-1,the reduction ability of strain Xiang 66 were better than those of other three strains, the scavenging rate of strain Rida to ABTS⁺ radicals was 39.79%,higher than that of the other three strains, DPPH· scavenging rate of strain L135 were better than those of the other three strains, with EC₅₀ of 3.53 mg·mL^-1,respectively, the scavenging rates of hydroxyl free radical by 808 were higher than the others, and the antimicrobial activity of exopolysaccharide from strain 808 was higher than that of the other three agaricus blazei strains.