Abstract: One full-scale lightweight steel frame (LSF) specimen and three full-scale prefabricated lightweight steel frame-light steel keel-lightweight concrete shear wall (LFSW) structure specimens were designed and fabricated to study the effect of two assembly methods (embedded installation or external installation) and the two light steel keel distribution modes (frame or truss) on the seismic behavior of the LFSW structure. The failure modes and damage evolution process were studied, and the hysteretic characteristics, ultimate strength, deformation capacity, stiffness degradation, energy dissipation and strain characteristics were analyzed by the low-period cyclic load experiment. Results show that the lightweight steel frame and light steel keel-lightweight concrete shear wall has good mutual work performance. Compared with LSF specimen the ultimate strength of LFSW specimens are improved by 204.7% to 210.4% and the initial stiffness improved by 257.3% to 512.5%, and the deformation capacity and energy dissipation are also significantly improved. The self-tapping nail joints of embedded wall and high-strength bolt joints of external wall both have reliable mechanical performance, and the mechanics characteristic of two seismic fortification lines was discovered on LFSW structure. The calculation model of ultimate strength was established based on Simplified Plastic Model and Softened Strut-and-Tie Model, the proposed practical calculating method can evaluate the ultimate strength favorably.