Abstract: Based on the experimental results of I section combined steel-lead dampers (CSLD), the hysteretic model of I section CSLD is proposed and the seismic responses of the structure with CSLD are simulated to study the hysteretic performance and the control effect. Firstly, the finite element model is proposed. With the help of finite element analysis, the geometrical parameters of CSLD are designed by Uniform Design method. Then the bilinear hysteretic model of the CSLD is proposed, whose characteristic parameters are yield strength, elastic rigidity and stiffened rigidity. A regression analysis yields the equation relating the characteristic parameters of the model and the geometric parameters of the damper. The proposed model is simple and can be conveniently applied for practical purposes. The model agrees well with the experimental results, indicating the equation of characteristic parameters is reasonable. Finally, a simulation is conducted to examine the seismic responses of CSLD vibration control system. The simulation results show that the CSLD has favorable vibration control effect.