We have proposed the rehabilitation system of RC frame using hysteretic damper installed in beam lower space. To make damper effective, it is desirerable to make the damper strong. The system has limitation of damper’s strength because shear strength of RC frame joint is very low in ordinary old building. To solve the difficulty, we propose the outer steel frame with the damper installed in beam lower and upper space. We performed the cyclic loading tests on scaled RC frame with the outer steel frame with dampers to show the availability of the present system. From these results, conclusions and remarks are drawn as follows. 1) Four hysteretic dampers yield within small story drift, so that the system absorbs the seismic energy effectively. 2) The system improves the shear strength of RC frame, so that we can install the stronger damper.