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.