Abstract: The vertical displacement response of large cantilevered roof structure, which is sensitive to wind load, is easy to exceed the code prescript. For mitigating wind-induced vibration and improving structure vibration behavior, the viscoelastic dampers are a good choice to control the response of the large cantilevered roof structure. On the procedure of vibration control design, model strain energy method is pivotal to get design parameters. When the material loss factor is high, traditional modal strain energy method may produce relative great error. A revised modal strain energy method is presented to improve the analysis accuracy. The calculation formula of vertical control force, the equivalent stiffness and the equivalent loss factor of energy dissipation brace are introduced. With the guide of design procedure, the wind- induced vibration control design for a large cantilevered steel roof structure is given. The design procedure of wind - induced vibration control for large cantilevered steel roof structure is very convenient and practical for structure engineers.