In this paper,based on the actual case of metro shield lateral crossing below the existing railway bridge,the influence between the shield construction and the railway bridge was investigated.The regulations and provisions on the settlement of bridge in different codes were introduced.Move over,analysis was made on the settlement of the shield tunneling across the existing railway bridge by means of 3D FEM in two cases,which used and no used composite anchor pile reinforcement and the following technical countermeasures were proposed:firstly,pre-reinforcement was made for the ground surrounding the pile of the bridge where shield passing through,so as to improve the ground's stability and isolate protection of the bridge pile;secondly,strengthened segments with preserved grouting holes are adopted in the tunnel design;thirdly,the construction parameters should optimize,strengthen monitoring and reasonable information construction should be used.