The deformation and internal force of shield tunnel in saturated sandy soil layer may be changed due to liquefaction, which may lead to tunnel failure. However, the influence of liquefied strata on overlapped tunnel may be aggravated by the interaction between structures.Based on engineering example, a three-dimensional model was established by using the software Midas GTS to analyze horizontal and vertical seismic dynamic time history of the tunnel with liquefiable soil. It analyzed the different influences of different positions and uneven distribution of liquefied strata on the tunnel. The internal force and deformation of the tunnel structure in liquefiable and non liquefiable conditions were compared. The treatment effect of stratum reinforcement on liquefied stratum is studied. The internal force and deformation of the tunnel in liquefiable condition are increased to a certain extent. It cause a great impact when the liquefied strata are located at the bottom of the tunnel, or it is not uniform. The vertical seismic action mainly affects the vertical deformation of the tunnel. it is better to use radial grouting to reinforce the ground when the liquefaction degree is moderate.