本文以茶新菇为原料提取水溶性多糖，同时在体外进行多糖对氧自由基的效应实验，实验结果表明，当为NaOH浓度为0.77 mol/L，提取时间为2.71 h，料液比为1:88.22（m/v）时，水溶性多糖的最高提取率为2.950 %，茶新菇水溶性多糖对氧自由基具有清除效果，其EC50为1.5 mg/mL。

In this paper, a water-soluble polysaccharides was extracted from Agrocybechg Fruit-body was studied and its elimination effect in vitro on the superoxide radicals O2 - was investigated. The results showed that the concentration of NaOH, extracting time and the ratio of the powder to the water were 0.77 mol/L, 2.71 h, 1:88.22，respectively, under which the extracting rate of the polysaccharide reached 2.950 %. Besides, the achieved water-soluble polysaccharide showed great elimination effect on O2- with the EC50 value being of 1.5 mg/ml.