Viscoelastic (VE) dampers are a kind of effective passive vibration control device and widely used to attenuate structural vibration. In this article, experimental study and multiscale modeling analysis on the VE damper for reducing wind-excited vibration are carried out. First, an experimental study on VE damper is conducted to reveal the dynamic properties of VE damper. The experimental results show that the dynamic properties of VE material are influenced by excitation frequency and insignificantly affected by displacement amplitude, and the VE material has good energy dissipation capacity. Second, the damping mechanism of VE damper is analyzed from micro-perspectives by considering the influence of cross-linked and free molecular chain networks. Then, a novel type spherical chain network model based on the chain network microstructure is proposed. The proposed model is verified by comparing the experimental data and the mathematical results, which indicates that the proposed model can accurately describe the dynamic properties of VE damper affected by different temperatures, frequencies, and displacements.