Abstract: Hot water was used for extracting polysaccharide from pitaya flower.Heating temperature,the ratio of solid to liquid,and heating time were three factors used separately in single factor test to analyze the influence of various factor on extraction efficiency.Orthogonal experiment design L9(33)was applied to optimize the extraction parameters.The results showed that,with ratio solid∶liquid in 1∶35and extraction temperature at 90℃for 3h,the best extraction efficiency of polysaccharides from pitaya flower was obtained for 55.87mg.g-1.