Abstract: In order to inhibit pigment substance in the process of preparation of wheat gluten polypeptides,the law of inhibiting browning stain was studied by experiment of adding different browning inhibitors. It was found that browning inhibitors could effectively control the brown stain in hydrolysis of wheat protein and decrease the color value under the certain conditions. The results showed that the factors affecting the inhibiting browning rate of citric acid, L- cysteine, glucose oxidase were offered in turn, and the three browning inhibitors had significant influences on browning stain( p <0.05). The optimal process conditions were obtained by Box-Behnken design as follows:0.02% glucose oxidase,L-cysteine 0.75%,citric acid 0.16%,under the condition of theoretical browning inhibition rate was up to 44.35%. The model of the two linear regressions was good based on the range of the experiment,the inhibitors could inhibit browning in wheat protein enzymolysis process under the certain of conditions,reduce the formation of pigment materials,and did not influence the degradation rate of wheat protein.