Abstract: Magnetorheological (MR) damper performance experiments were conducted. Based on the MTS 793 software system, shaking table tests of a five-story steel frame model with two different MR dampers were carried out using different control strategies, including two passive ones and some semi-active ones based on H_∞ static output feedback. The results experimentally demonstrated that the control system is effective for the five story model structure with all the control strategies. When off-state force corresponding to zero input current of MR damper was sufficiently large, MR damper in the case of on-stage almost does not move. When off-state force corresponding to zero input current of MR damper is small, the performance of MR device in the case of on-stage is superior to that of off-stage. The semi-active control system is not considerably more than the passive systems. Experimental results also show that MR damper must match the structure, which is particularly important for the semi-active seismic response control.