Abstract: In the process of construction, impounding or action of earthquake, the solid-fluid coupling has a significant influence on the static and dynamic responses of earth-rockfill dams, which should be considered in the seismic analysis. Taking the Nuozhadu high earth-rockfill dam as an example, static and seismic analyses are conducted by using the solid-fluid coupling method. The Mohr-Coulomb elasto-plastic model is employed to describe the mechanical properties of dam materials. The construction of the dam and the impounding of the reservoir are simulated in the static analysis, then on the basis of the static stress field, the dynamic response of the dam during an earthquake is investigated using the fully-coupled nonlinear method. The evolution of residual deformations and the accumulation and dissipation of excess pore water pressure can be calculated more reasonably. The results show that the excess pore water pressure accumulates gradually with earthquake, and the maximum value occurs at the bottom of core. The acceleration amplification reaches the maximum at the crest as a result of whiplash effect. The horizontal and vertical permanent displacements both reach the maximum values at the dam crest.