Metro stations and sections use different construction methods to cross the same overpass and retaining wall for many times, and it is rare that the boundary interface of structure and construction method is located in the continuous beam section with complex stress of the bridge. To study the impact and sensitivity of various construction methods and stages on overpasses and retaining walls, the author takes the Renmin University Station and the section of Renmin University Station and Suzhou Bridge Station of Beijing Metro Line 12 under complex environment as the overall analysis object, and adopts empirical formula and finite Meta computing analysis methods to study the impact of various construction stages and measures on bridges and retaining walls before and after implementation, and compares the calculated theoretical values with the actual monitoring values during onsite construction. The results show that: (1) Comprehensive treatment measures such as taking measures inside and outside the tunnel, coordinating the construction deployment on the north and south sides, strengthening monitoring, and controlling key processes are effective, 〖HJ2.3mm〗especially the use of unconventional measures such as pile bottom grouting, bridge active lifting, and bearing platform transverse beams; It is proved that the design and construction plans of the station and section structures are reasonable and feasible. (2) The main structure of the station adopts the PBA construction method, with a large excavation section and complex process connection. The construction stage of the station main body has the greatest impact on settlement. (3) The settlement of the 1st axis bridge piles with isolation measures in the shield tunnel section is basically equivalent to other bridge piles, and the necessity of adopting isolation measures in similar projects is not significant. (4) The settlement trend and total settlement of the retaining wall at both the station and section are basically consistent with the ground settlement.