The seismic response of Tehri dam, located in the central Himalayan seismic gap, is simulated employing coupled pore fluid diffusion-stress-based finite element method (FEM). The initial stress state of the dynamic analysis is attained by conducting the static analysis of the dam with due incorporation of the embankment dam construction and reservoir filling data. Subsequently, the acceleration time history data of the 1991 Uttarkashi earthquake of Mw 6.8 is used as the input motion at the base of the dam. First, a modal analysis is carried out to analyse the dam vibration characteristic, which gives the natural frequencies and the corresponding mode shapes of the dam. Further, mode-superposition response spectrum method, an inexpensive approximate method for preliminary design studies, is used to estimate the peak (linear) response of the dam to the earthquake excitation. The outcome indicates that maximum displacement of the dam occurs at the dam crest in the shear (first) mode. Peak displacement due to a Mw 8.5 earthquake, occurrence of which has high chances in the region, is found significant. Later, FEM-based dynamic implicit method is used to assess the seismic effect on Tehri dam. The displacement and acceleration time history within the dam body is examined. The tendency of the dam to liquefy is assessed by plotting the ratio of cyclic stress ratio (CSR) to cyclic resistance ratio (CRR). Some parts of the upstream shell section of the dam, which is below the phreatic line, is found susceptible to liquefaction. The ratio is higher at locations where the effective stress in the soil is less than the pore pressure developed.