This study examines the seismic activity about Koyna Concrete Gravity Dam, a structure essential for managing water resources, producing hydroelectric power, and preventing flooding. The dam, built in 1963, was tested by a 6.5 magnitude earthquake in 1967, prompting the construction of concrete buttresses for reinforcement. Despite these precautions, the dam’s seismic susceptibility remains an issue. This study will use advanced finite element modeling and historical ground motion data from the 1967 earthquake to better understand the dam’s dynamic response to seismic loading. The analysis looks at static and dynamic loading conditions, illustrating how the dam behaves during normal and seismic events. The modal analysis results are highly consistent with prior investigations, demonstrating credible modeling with percentage variances in time periods and natural frequencies ranging from 0% to 1.59%. Crest displacement study shows large movements during seismic events, with maximum displacements of 3.568 cm upstream and 3.161 cm downstream. Stress distribution visualizations indicate crucial structural evaluation locations, with stress values varying by up to 3.62% from previous analyses. These findings provide important insights into the dam’s performance during seismic events, aiding continuing efforts to improve its safety and reliability. By addressing its seismic susceptibility and guiding future risk assessment and mitigation techniques, our research supports the continued integrity and longevity of vital infrastructure in seismically active areas.