Abstract: To improve the seismic performance of the RC core walls,reinforced concrete composite core walls with concealed steel truss were proposed and systemically investigated.Two 1/6 scale core walls specimens, including a normal reinforced concrete core walls and a reinforced concrete composite core walls with concealed steel truss,were designed.The experimental research on seismic performance under cyclic loading was carried out.The load-carrying capacity,stiffness,ductility,hysteretic behavior and energy dissipation of the core walls were discussed.The test results showed that the seismic performance of core walls was improved greatly by the concealed steel truss.And the calculating results were found to agree well with the actual measured ones.