This paper aims to explore the effect of ultrasonic milling parameters on the surface integrity and corrosion characteristics of AZ31B, and diminish the surface roughness and raise the corrosion resistance of AZ31B. In this paper, the ultrasonic milling experiment of AZ31B was performed based on the CCD of RSM, and the electrochemical corrosion experiment was completed in PBS. After establishing the prediction model between process parameters (spindle speed, feed rate, milling depth and amplitude) and response targets (surface roughness, surface hardness and corrosion rate), then significance analysis was in progress and the relationships between four factors and three responses was discussed. Next, the influence of ultrasonic milling parameters on the , and corrosion characteristics of AZ31B was analyzed. Finally, the prediction model of response objective was optimized, furthermore, the optimum matches of factors was determined and verified by experiment. The results can be listed as follows:According to the regression model of , and , not only the F values were 11.45, 9.20 and 9.58 separately, which are greater than 2.424, but also all of these parameters’ P values were smaller than 0.0001. And for , and , the factors’ minimum of P values were , and respectively. By analyzing the influence of four factors and three responses in ultrasonic milling, the variation curves of surface roughness and corrosion rate under different parameters were obtained, besides values increases with the rise of amplitude. The greatest parameter’s matches were tested by trial, which showed that the error between the predicted output and the measured of roughness and hardness were smaller than 5% and was below 15%. The main conclusions:the model of , and has high accuracy, and can be used as the corresponding prediction model; the four parameters of ultrasonic milling have the greatest influence on , and for , and respectively. The corrosion characteristics and surface roughness of AZ31B have the closely relationship, in addition, the increase of amplitude leads to the increase of surface roughness and aggravates the corrosion of machined surface. The predicted values of , and are in good agreement with the experimental values.