In order to study the seismic capacity of reinforced-block-masonry shear walls, the confined masonry and the confined concrete are put forward as boundary member material to increase the ductility of shear walls. Through the calculation of displacement ductility, the key factors which influence the displacement ductility of shear walls are obtained, they are axial-compression-ratio, shape ratio, limit compress strain of masonry, etc. The axial-compression-ratio limitation is proposed for masonry walls with different confined boundary members. The response modification factor is introduced to evaluate seismic capacity of the masonry walls, and the seismic capacity of the masonry walls with the suggested confined boundary members is specified. The response modification factor of the masonry walls is compared with ground motion ratio under different seismic level. It is concluded that the shape ratio of the masonry walls must be restricted to meet seismic requirements of China's codes.