Objective:To establish an optimum method of extraction of polysaccharide from Dendrobium henryi.Method: Tradition water leach

cellulose enzyme

ultrasonic assistant and microwave assistant extracting procedures were used for polysaccharide extraction

and the phenol-sulfuric reaction was used for the determination of polysaccharide.Result:The optimum condition of extraction of Dendrobium polysaccharide was as follows: solid to liguid ratid was 1∶30 with enzyme of 200 U·mL-1 extracted for 2 hours at 50 ℃

pH4.5 in cellulose enzyme extraction;the third-gears microwave power was used for 8 minutes pretreatment

then extracted at 80 ℃ for 1.5 hours in the microwave assistance extracting;the ultrasonic power 300 W and 6 minutes of pretreatment were used with solid to liquid ratio of 1∶ 30

then extracted at 80 ℃ for 1.5 hours in ultrasonic assistance extreacting;and extracted at 80 ℃ for 1.5 hours with solid to liquid ratio of 1∶ 30 in tradition water leach extracting.Conclusion: The highest yield for Dendrobium polysaccharide extracted occurred in cellulose enzyme extracting

which was the preferred alternative.Tradition water leach extracting should be combined with ultrasonic assistant and microwave assistant extracting.