This study focuses on the seismic behavior of Shear Panel Dampers (SPDs), which are introduced to improve the seismic performance of a benchmark steel arch bridge. Four schemes of seismic upgrading models are considered for different ground types. Then dynamic analyses are carried out with 12 patterns of Level 2 earthquake ground motions, and seismic performances of the upgrading models are compared with the original structure without dampers. The influence of repeated earthquakes is also examined by using the same ground motions repeated for three times. Based on the seismic demands of SPDs obtained from dynamic analyses, the necessary capacity values of SPDs with safety margins to against repeated earthquakes are proposed.