Maximum displacement response of the hybrid system composed of slip-type and elasto-plastic type restoring characteristics to clarify the retrofit effect of elasto-plastic type restoring characteristic on a slip-type restoring characteristic structure. As results, the composed system is effective under 1.0 s natural period when the elasto-plastic type restoring characteristic is over 10% of base shear. The maximum displacement responses of composed system with 5% base shear of elasto-plastic type restoring characteristic are abided by the property of displacement conservation. The 5% base shear of elasto-plastic type restoring characteristic retrofits a slip-type restoring characteristic structure effectively.