This study revealed that seismic retrofit technology which has to conduct seismic retrofit work after removing facing walls from a reinforced concrete structured building constructed with masonry walls and facing walls, bears disadvantages of additional costs both for removal of facing walls and for brick masonry and possibility to incur the secondary damage from collapse of facing walls. Therefore, this study aims to develop a seismic retrofit technique and examines its performance which can yield sufficient seismic retrofit effect without additional retrofit of facing walls by forming a pile-bent reinforced concrete walls with facing walls after removing masonry walls.