Abstract: The removing efficiency of protein was investigated with respect to four variables including ethanol concentration, temperature, liquid-to-solid ratio and time. On the basis of a series of single factor experiments, a polynomial regression model equation was fitted by the combined use of Box-Behnken experimental design and regression analysis. By analyzing the regression model using response surface analysis, the results show that the optimized conditions is ethanol concentration 69.15%,temperature 50.19℃, liquid-to-solid ratio 50.88(mL/g),and time 39.17min,which results removing protein efficiency (92.00±0.04)%, close to the predicted value of 92.07%.Therefore, the established regression model is feasible and has good prediction capability in the process of capsaicin detection.