In order to optimize the extraction process of Grifola frondosa polysaccharides,with Grifola frondosa fruit body as the research object,the extraction rate of polysaccharides from Grifola frondosa is determined by sulfuric acid-phenol titration method combined with ultraviolet spectrophotometry.On the basis of single-factor and multi-level experiment,response surface methodology and Design-Expert software are used to select three factors such as extraction time,extraction temperature and extraction liquid-solid ratio.A three-level experimental scheme is set up to optimize the extraction process.The results show that the optimum extraction conditions are as follows:extraction time is 1.9 h,extraction temperature is 80 ℃,extraction liquid-solid ratio is 37∶1(mL/g),under such conditions,the extraction rate of polysaccharides is 14.45%.Antioxidant activity research results show that the polysaccharides from Grifola frondosa have good scavenging capacity on DPPH free radical and hydroxyl free radical.Within a certain range,the antioxidant activity increases with the increase of polysaccharides concentration.