In order to forecast and control the deformation of existing underground tunnels induced by canal excavation,based on a metro-crossing canal excavation example of Zhejiang section of the Beijing-Hangzhou Canal in Hangzhou,we study the theoretical deformation values of the tunnel structure under both common excavation scheme and the scheme with certain heave resistance measures.A series of construction measures are attempted,including block excavation,foundation reinforcement and uplift frame structure to resist the shift of underlying metro line 1,based on all the geological conditions and design requirements that have been known.Moreover,a 3D finite element model is established to simulate the whole excavation process,and the results prove that the measures designed for controlling the deformation of subway shields are effective and can fulfill the requirements of safety operation of metro tunnel.