In order to study the influence of foundation pit excavation on the structure of adjacent existing subway stations, taking a development project in Jinan as an example, the influence degree is determined, and a three-dimensional model is established by MIDAS finite element software for numerical simulation analysis. The results show that the influence level of external operation of foundation pit on the existing station structure is special, and the maximum horizontal displacement and maximum vertical displacement of the existing station structure caused by foundation pit excavation are 7.11 mm and 14.53 mm respectively. The settlement and displacement of the existing station in the process of foundation pit construction meet the specification requirements, which can be used as a reference for similar projects.