Objective: To optimize extraction technology of total flavonoids in Geranium wilfordii. by central composite design/response surface methodology. Method: Independent variables were ethanol concentration

reflux time

the amount of solvent and reflux temperature

dependent variable was extraction rate of total flavonoids

linear or no-liner mathematic models were used to estimate the relationship between independent variables and dependent variable

response surface methodology was used to optimize extraction technology

and prediction was carried out through comparing the observed and predicted value. Result: Regression coefficients of binomial fitting complex model was as high as 0.960 9

optimal extraction technology conditions were as followings:extracted 2 times with 35 times the amount of 65% ethanol at 90 ℃

70 min per time.Bias between the observed and predicted value was-1.25%. Conclusion: Central composite design/response surface methodology was convenient and highly predictive for optimizing extraction technology of total flavonoids.