Abstract: To optimize the deproteinization conditions from crude polysaccharide of pholiota nameko in order to improve reduction efficiency. The technology of removal of proteins frome nameko polysaccharides by richloroacetic acid method was optimized using response surface methodology (RSM) . On the basis of single factor experiments. The polysaccharide retention yield and the removal protein yield were used as the responsive values. Three-variable and three-level experiments design were developed by Box-Benhnken central composite design method. The optimized process conditions was obtained by the method of response surface analysis. Results indicated that the optimum technological conditions were as follows:the ratio of material to liquid 1∶3, the time of removing protein 50 min, the best concentration of trichloroacetic acid (TCA) 6%. Under the optimal conditions:the predicted and experimental retention yields of polysaccharides were75.40% and 75.08%, the predicted and experimental removal yields of proteins were 84.39% and 84.16%.Therefore, there was a good accordance between the predicted value and observed value.