In recent years, the construction of urban metro has developed rapidly. However, the construction of subway tunnels often disturbs the surrounding strata, and in severe cases, it can cause accidents such as surface subsidence and the collapse of buildings (structures) above the tunnel. Therefore, how to ensure the safety of existing buildings (structures) above the tunnel during the shield tunneling process and reduce the impact of subway construction on the surrounding environment has become the key to subway tunnel construction. This paper relies on the project of Xi'an subway's shield tunneling under the Heihe Water Aqueduct. By assessing the current status of the underwater Water aqueduct, setting up a test section to simulate tunneling, strictly controlling the formal tunneling parameter settings, and conducting effective monitoring, the soil stability during the tunneling process and the safety of the shield tunneling under the Heihe Water Aqueduct were ensured. Combining the field measured data and using statistical analysis, the research on the deformation of the strata caused by shield tunneling and the shield tunneling parameters was conducted. The study found that shield tunneling parameters have a significant impact on soil stability, and there is also a certain correlation between shield tunneling parameters. Finally, the full-process technical means of shield tunneling under the Water aqueduct were summarized and analyzed to form a set of practical prevention and control measures, which provides guidance for the implementation of similar projects in the future.