Energy-dissipating devices have been effectively used for seismic control of structures over several decades, particularly on bridges and on tall and slender buildings. This is because they reduce the dynamic responses and acceleration due to wind and seismic events by converting the mechanical energy of the structure into heat energy without affecting the architectural beauty of the structure. Study suggests that among the available passive control devices, viscous mass damper is the most promising. For any particular structure, benchmark problems are proposed to evaluate and compare among the various control strategies. Benchmark problem on highway bridge is proposed as per 91/5 highway over-crossing in Southern California. The primary focus of this study is to assess the seismic performance of modified viscous mass damper based on the evaluation criteria considering six specified ground motions and salient responses of the bridge like shear at base, moment at base, displacement of deck, etc., and the performance of modified viscous mass damper is evaluated. The findings suggest that modified viscous mass damper dissipates a part of the seismic energy and effectively reduces the relative motion between the base and superstructure and then of the ground. A detailed analysis is performed to obtain the dissipation of high energy per unit time to evaluate the applicability of modified viscous mass damper that can reduce the generated seismic energy during an earthquake and structural stress transmitted to the superstructure.