With the increasing demand for transportation construction in coastal areas, tunnel safety research is becoming increasingly important. Previous studies take less account of the nonlinear wave and current action under the sloping seabed terrain. Furthermore, there are few researches on the additional deformation of shield tunnel lining caused by wave‐current dynamic pressure. In this paper, according to the interaction theory of Stokes third‐order nonlinear wave and uniform current and Biot's dynamic consolidation equation, the excess pore pressure response of sloping pure seabed under the wave‐current action is obtained. The excess pore pressure reflected by the tunnel is acquired using the seepage continuity condition on the permeable lining surface. Considering the residual excess pore pressure caused by the cumulative effect under the cyclic action of seepage force. Then the distribution law of seepage pore pressure around the shield tunnel in the sloping seabed under the wave‐current action is obtained based on the superposition principle. The displacement response of tunnel lining during the long‐term service period is obtained by combining the exponential decay model. Moreover, the accuracy of theoretical analysis is verified by experimental monitoring data and numerical simulation, and the hydraulic parameters, seabed parameters and tunnel parameters are analyzed.