The optimization of the extraction of Lily Polysaccharides was studied in this paper.On the basis of the single-factor experiments and according to the central composite experimental design principles,the method of Response Surface Method with 3 factors and 3 levels was adopted.Then the factors influencing the technological parameters were determined by means of regression analysis.Response surface and contour were finally graphed with the extraction rate as the response value.The results showed that the op...