Abstract: In order to optimize extraction conditions of polysaccharides from Cortex Lycii. We built quadratic response surface regression model and optimized the ratio of liquid to material, extraction time and temperature by using Box-Behnken central composite design and response surface methodology on the basis of single factor experiment. The experiment results show that the optimal conditions are: the ration of liquid to material 24:1 mL/g, the extraction time 2.5 h, and the extraction temperature 71 ℃. Under the conditions, the extraction rate of polysaccharides from Cortex Lycii is 16.9020%.