Objective: To optimize ultrasound-assisted extraction technology of polysaccharides from Amomum villosum by response surface analysis. Method: On the basis of single-factor tests

with yield of polysaccharides from A. villosum as index

quadratic polynomial regression equation of polysaccharides yield was established by a three-factor and three-level Box-Behnken Design with solid-liquid ratio

extraction time and temperature as factors

then the established model was analyzed by response surface methodology to obtain optimum extraction process.The content of polysaccharides was determined by UV. Result: Optimum extraction conditions were as follows:extracting time 71 min

solid-liquid ratio 39: 1 and extraction temperature 78 ℃.Under these conditions

the estimated and observed values of yield of polysaccharides were 13.22% and (13.04±0.36)%

respectively. Conclusion: Compared with traditional water extraction

ultrasound-assisted method had advantages of time-saving and efficient

this study could provide experimental basis for the follow-up research and development of polysaccharides in A. villosum.