In this study, the interaction relationship and seismic performance efficiency of composite shear walls were investigated. A previous experiment was reviewed to understand the failure mechanism of the composite shear wall, and the key parts of the structure were explored via simulation. Based on the simulation results with different parameters, the seismic performance sensitivity and interaction relationship of the horizontal corrugated steel-plate composite shear wall were analyzed. From a related analysis, the seismic performance efficiency of a composite shear wall was divided into five levels; the evaluation index was the column-to-plate shear ratio. The calculation formula for the composite shear wall was modified from the viewpoint of interaction. The results showed that when the shear ratio was greater than 1.45, the column had sufficient restraint to improve the efficiency of the corrugated steel plate; the composite shear wall had an optimal interaction. Additionally, the theoretical calculation of the lateral bearing capacity considering the interaction relationship was more accurate.