The objective of the proposed hybrid control system is to reduce the response of buildings against the earthquake ground motion using the relatively smaller magnitude of active control force without sacrificing performance against mild to moderate types of earthquakes.The proposed hybrid control system is composed of shape memory alloy passive dampers to reduce the earthquake-induced forces in the structure and an active mass damper to further reduce the responses of building frames. The performance of the proposed hybrid control system is investigated and compared with that of an active control system. It is shown that the theoretical/numerical result of the proposed hybrid control system is very effective in reducing the response of building frames subjected to earthquake-induced excitations. The concept is analytically investigated by numerical simulation of the proposed hybrid control in an idealized eightstory concrete building frame model.