In order to investigate the wind-induced responses of a tower 838 meters high under the designed wind speed, multi-degree-of freedom aero-elastic model wind tunnel tests were carried out. It was found that the first-order and the second-order frequency inaccuracy of the model, which was measured from the free vibration test, were less than 1% and 28%, respectively, the first-order damping ratio was about 2%, and the translational vibration mode shape was consistent with the actual structure. Wind tunnel test result has shown that the maximum wind-induced dynamic displacement is 0.89m, which is in the standard allowable range. But the wind-induced acceleration of 10 years', 50 years' and 100 years' return period exceeds the specification threshold with the amplitude of 16%, 23%, 29%, respectively. What's more, the lateral response increases remarkably by first order vortex induced vibration，in which the contribution of aerodynamic damping is close to 37%.And in order to ensure acceleration response under one hundred years' wind speed in the allowable range, the structural damping ratio must be larger than 2.9%.