Abstract: Composite shear walls incorporating concrete-filled steel and FRP tubes as boundary elements are a new type of hybrid structural members and have excellent mechanical and seismic performance. Combined with the results of quasi-static tests, the stress mechanism of the composite shear wall was analyzed, and the stress states of concrete-filled steel tube and FRP-confined concrete were analyzed and simplified. Thus, the calculation formula of ultimate bearing capacity of composite shear walls was established. Through a comparison with the experimental results, the correctness and applicability of the bearing capacity formula were verified, which provides a reliable theoretical basis for further research and application.