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Earthquake-induced liquefaction poses a risk of floatation of underground structures located in liquefiable soil deposits.This failure phenomenon generally occurs when the soil liquefies and loses its shear resistance against the uplift force from the buoyancy of the underground structure, such as tunnels and pipelines.In this paper, the seismic behavior of a shallow rectangular metro tunnel is investigated using an effective stress based soil-water coupling finite element method.The behavior of soils are described by means of a cyclic elasto-plastic constitutive model in which, the stress-induced anisotropy, the density and structure of ground can be described in a unified way.The results showed a matching uplift response of the structure, acceleration, and pore pressure and ground displacement.Special emphasis is given to analyze the result of excess pore water pressures, stress path, acceleration, deformations.The displacement of soil around the structure was confirmed to resemble a flow mechanism from two sides of the structure to its invert which is different from the global circular flow mechanism of circular tunnels.