Abstract: Haining Xiashi seismic station is located in the civil air defense cave in Xishan Park, Xiashi Street, Haining City, Zhejiang Province. During the construction of the station, the first problem is the poor quality of rock mass. When the tunnel is excavated to a depth of more than 2 m below the ground, the rock is still porous and broken; The second is the problem of high chamber humidity (>95% Rh). Finally, in the case that it is impossible to use rock pier to build the platform, the large area concrete instrument pier is poured and the cavern environment is transformed to reduce the humidity of the cavern, achieve thermal insulation and constant humidity, and improve the observation environment. So far, the station has been in operation for more than ten years. From the current situation, the observation data of the station is stable and continuous, and the solid tide is clear, which has achieved the expected effect of the station transformation. This paper summarizes the experience gained in the reconstruction process of Haining Xiashi Seismic Station, and provides reference for the construction of topographic deformation observation stations in some civil air defense and civil caves without rock piers.