Abstract: Response surface methodology was applied to optimize the extraction conditions of total triterpenes in potentilla discolor by microwave assisted extraction. Based on the results of the single factor experiments,the effects of three independent variables(extraction time,solid-liquid ratio and extraction power) on the triterpenes yield were investigated by a Box-Behnken experimental design of three factors and three levels. A quadratic polynomial regression equation of the forecasting model was set up. And the optimal extraction parameters to obtain the highest triterpenes yield were as follows:the ratio of liquid to solid was 20 m L/g with ethanol as solvent,microwave power was 381 W,and extraction time was 116 s. The average experimental triterpenes yield under the optimum conditions was found to be 1.305%,which agreed with the predicted value of 1.252%.This method was promising in the extraction of total triterpenes in potentilla discolor,which had advantages of less extraction time,convenient control,energy conservation and environmental protection