Abstract: ObjectiveIn the present study, response surface methodology was applied to optimize the process condi-tions for the microwave-assisted extraction of total flavonoids from Paris Polyphylla, in order to improve the extraction yield of total flavonoids and provide technique support for actual production. MethodBased on single factor experiments, three major parameters including alcohol volume fraction, microwave power and liquid-solid ratio were optimized using Box-Behnken certral composite design, in a bid to select the optimal process parameters for total flavonoids extraction from P. Polyphylla. ResultThe regression model based on extraction of total flavonoids from P. Polyphylla(Y), ethanol volume fraction(A), liquid-solid ratio(B) and microwave power(C) was as follows:Y=4.90+0.30A+0.51B+0.48C-0.19AB+0.44AC+0.24BC-0.85A2-0.83B2-0.55C2(R2=0.9734). The fitting degree was high. The three parameters and interaction between ethanol volume fraction and microwave power had extremely significant influence on total flavonoids extraction yield (P<0.01). The optimal extraction conditions were as follows: ethanol volume fraction 50%, liquid-solid ratio 17:1 and mi-crowave power 528 W. Under such conditions, the extraction yield was 5.28 mg/g. The relative error was 1.93% compared to the predicted yield (5.18 mg/g). ConclusionParameters of microwave-assisted total flavonoids extraction from P. Poly-phylla optimized by response surface methodology are feasible, which can be applied to actual production.