Abstract: Response surface methodology (RSM) was adopted to optimize for the combination of ultrasonic and inhibitors to control the browning of fresh-cut purple sweet potato. On the basis of single factor experiment, selecting the intensity of ultrasonic, the concentration of L-Cys, CA and AA as independent variables, and purple potato Browning degree as the response value, the interaction of the respective variables and their influence on the browning degree were studied by using Box-Behnken experimental design and response surface analysis theory. The quadratic polynomial regression equation of prediction regression model was established, the results indicated that the optimal condition for Browning inhibition was obtained as follows:ultrasonic intensity was at 130 W, L-Cys concentration was 0.03%, the CA concentration was 0.20%, AA concentration was 0.06%. Under these conditions, the browning degree was 6.10±0.09, which was close relation with the predicated value.