Noting that in traditional study, the dynamic response of the tower structure under wind load is usually analyzed by explicitly applying equivalent force on nodes of the tower’s finite element model which may oversimplify the flow-structure interaction interface, this paper presents a fully coupled finite element study of the dynamic response of monopole steel tower. Coupled finite element analysis is used to model the interaction between the steel tower and the wind flow. The steel tower is composed of tubes and is modeled using solid element, while the wind flow is governed by Navier-Stokes equations for incompressive flow. Parameters such as the viscosity of the flow and boundary conditions (wind velocity at different height) are measured from experiments. At each time step of the calculation, winslow moving mesh is used to rezone the computational grid to ensure the accuracy. Simulation is given for studying the deformation pattern of the tower structure.