Abstract: Polysaccharides from pitaya peel were extracted by inner ebullition method. To investigate the effect of extraction yield of polysaccharides from pitaya peel, the six factors of desorption agent, the amount of solvent, the time of desorption, extraction temperature, extraction time and ratio of material to solution were assayed. Based on single factor experiment, design L₉ (3³)orthogonal test, optimization of extraction process of polysaccharides from pitaya peel. The result showed that the optimum process for extracting polysaccharides from pitaya peel by inner ebullition method was:the ethanol concentration for desorption 80%, the amount of desorption reagent 5 mL/g, the time of desorption 15 min, the extraction temperature was 90℃.The ratio of material to solution was 1:25 (g/mL), the extraction time 6 min. The yield of polysaccharides from pitaya peel was 5.81%.The inner boiling methods has process conditions was stable in extracting polysaccharides from pitaya peel, and has the advantage of short time, easy operation, non-toxic and pollution-free, better effect.