Abstract: A steel structure with “dual functions” metallic damper was tested on shaking table to study the dynamic characteristic and seismic responses, especially the effect of this kind of damper on seismic behaviors of the structure. A frame structure model was made with ADPL language in ANSYS program. Seismic responses of the structure with and without metallic damper were discussed and compared. The results of tests and calculations show that the metallic dampers with “dual functions” presented here not only provide certain stiffness in normal using, but also are of good ability of seismic energy dissipation.