With the help of finite element software ABAQUS, the numerical analysis results of the finite element model of the masonry walls were compared with the experimental results to verify the reliability of the finite element simulation. Based on this, the effects of the cast-in-situ floor slabs, the strength of mortar, the cross-sectional dimension of ring beams, the vertical compressive stress on the top of walls, and the opening and aspect ratios of walls on the seismic performance of masonry walls were investigated. The results show that the cast-in-situ slabs, the constructional columns and ring beams form a complete structure, strengthening the constraint on the wall sheet and reducing the damage. The bearing capacity and ductility of walls increase with the increase of mortar strength. Appropriate cross-sectional dimension of ring beam and vertical compressive stress on the top of walls can effectively reduce the damage of masonry walls. The bearing capacity and displacement ductility of walls decrease with the opening of walls. The bearing capacity of walls decreases with the increase of the aspect ratio of walls. At the same time, the main failure mode of walls changes from shearing failure to bending failure.