Magnetorheological damper (MR damper) has been expected to control the response of civil and building structures in recent years, because of its large force capacity and variable force characteristics. In this paper, a series of real-time hybrid test was conducted and the results of real time hybrid tests were compared to those of shaking table tests. To determine the control force of the MR damper, skyhook control and sliding mode control theory were employed. As the results, the validity of real-time hybrid test was verified. This paper describes the capability of MR damper to control the structural response.