Abstract: The magnetorhrological damper (MRD) that uses MR fluids to provide controllability is one of the most promising semi-active devices to control structural vibration, which is available to be attached to Lead-Rubber Bearing (LRB) so as to form a base-isolated structure. Three kinds of such hybrid schemes of MRD and LRB were thus proposed with dynamic analysis set up. A kinetic differential equation was derived and a dynamic time history analysis was made. Taking a 7-story frame as example, the seismic response analysis was made for the proposed three kinds of hybrid schemes according to the theory of instantaneous optimal control (IOC) algorithm individually. Compared with the single LRB base-isolated structure, all the three hybrid schemes present clearly the effective controllabilities of seismic response especially the scheme 3.