The construction of new shield crossing several existing tunnels is a new type of underground space layout in recent years. The process of crossing the existing tunnel, which make the ground surface sink, but also affect the deformation of the existing tunnel. For two kinds of typical construction methods of up-crossing and under-crossing, the 3D elastoplastic FEM was applied to analysis the dynamic construction process. A modified Peck equation was proposed to predict ground settlement according to some results. The results showed that when interval among all tunnels are in the influenced range, a secondary disturbance is caused by shield advance and greater influence will be made on the existing tunnels. During the construction of up-crossing, ground settlement turns to be larger, the existing tunnels have a tendency of upward moving. Whereas the under-crossing makes a smaller settlement with a tendency of subsidence. This research provides some theoretical basis and prophase guidance for practical engineering construction.