Abstract: Objective: In order to control the deformation of the newly built foundation pit and reduce the impact of excavation on adjacent subway tunnels, it is necessary to explore the deformation control effect of the servo steel support system on the foundation pit and adjacent subway tunnels under the dual control method of axial force control and displacement control (hereinafter referred to as the ′dual control method′). Method: Based on a foundation pit project in Hangzhou, a numerical model of the foundation pit and adjacent subway lines is established. The servo steel support system axial force simulation scheme and displacement control scheme in ′dual control′ are proposed, corresponding calculation steps and monitoring conditions are set. The settlement and deep horizontal displacement of the foundation pit under six servo schemes are compared. The influence of different axial force control values and single displacement change control values on the deformation of the foundation pit is analyzed, and then the servo steel support system setting scheme for this project is obtained. Based on this plan, the simulated and actual monitoring values of deep horizontal displacement of foundation pit soil, ground settlement of foundation pit, and settlement of adjacent subway right line tunnels are compared，so as to analyze the control effect of servo steel support system deformation. Result &Conclusion: The deformation control effect of the double\|layer support servo steel support system is better than that of the single\|layer servo steel support system. In the control indicators of the ′dual control method′, an increase in the axial force control value can significantly reduce the maximum horizontal displacement and ground settlement of the retaining structure. The change in the control value of a single displacement change has little effect on the final deformation result. Therefore, the servo steel support axial force system under the ′dual control method′ can effectively control the deformation of the foundation pit and protect the safety of adjacent existing subway tunnel structures.