In order to better analyze the changes of parameters such as sidewall stress and deformation during tunnel excavation, the D-P criterion model was used to set the material properties of the rockmass, and the life and death unit excavation method was used to understand the tunnel sidewall stress during the whole process. In addition, a multi-objective optimization method for sidewall stress and strain based on response surface was established. The key parameters affecting the stress and strain of the sidewall are selected based on the sensitivity. The RSM was used to establish the response surface of the variable and multi-objective function. Multivariate regression model was used to analyze the interaction of parameters affecting sidewall stress and strain. Finally, the optimal combination of reducing sidewall stress and strain that meeting the tunnel design requirements was determined . The results showed that the main stress changes were concentrated in the second step of excavation. During the excavation, the peak and direction of stress and strain changed greatly. The stress peak changed from 9.7×105 Pa to 1.47×106 Pa, and the direction changes from sidewall to outward. The sidewall is inward, which easily leads to the collapse of the sidewall of the tunnel. The combination of the length and width of the section 1.35 m and 2 m with the optimization of response surface analysis leads to the stress peaks fell 10.01%. The life and death excavation method combining with the response surface provides an effective way for the well design optimization analysis and tunnel excavation process parameters analysis.