Abstract: The excavation and unloading of foundation pits will lead to the deformations of the surrounding soil and the adjacent subway tunnels. The excessive deformation will seriously endanger the safe operation of subway tunnels. In order to study the influences of excavation of deep foundation pits on the deformation of the adjacent double-line subway tunnels, based on the foundation pit project adjacent to an operating tunnel in Hangzhou, combined with the monitoring data of the construction site, the deformations of the foundation pit and the tunnel during the whole process of excavation of foundation pit are measured and analyzed, and the relationship between the deformation of the foundation pit and the deformation data of the adjacent subway tunnel is explored.