Objective: To optimize extraction technology of total flavonoid from root of Arctium lappa. Method: With extraction rate as index

effect of different factors on extraction technology was investigated by single factor test

including the concentration of ethanol

solid-liquid ratio

crush size

extraction times

ultrasonic time

temperature and power;Orthogonal test was use to optimize ultrasonic extraction conditions of total flavonoid from root of A. lappa with extraction time

ethanol concentration

ultrasonic power and crush size as factors

and test data was statistical analysing by SPSS software. Result: Ethanol concentration

ultrasonic time

ultrasonic power and crush size were main factors

which influencing extraction effect of total flavonoid.Optimum extraction technology was as follows:crush size of A. lappa root of the most coarse powder

extracted 3 times with 20 the amount of 60% ethanol at 60℃

40 min each time

ultrasonic power 60 W. Conclusion: Optimized extraction technology was stable and feasible

it could be suitable in industrial production.