This study investigates the mitigating effects of a TMD on the structural dynamic responses of Taipei 101 Tower, under the action of winds and remote (long-distance) seismic excitation. To begin with, the optimal parameters of the TMD in Taipei 101 Tower are first determined. Then a finite element model of this high-rise building, equipped with a TMD system, is established. A detailed dynamic analysis is conducted accordingly, to evaluate the behavior of the structure-TMD system. The simulation results obtained are compared with the wind tunnel test data and the recorded field measurements. The accuracy of the established computational frameworks is then verified. Findings of this study demonstrate that the use of the TMD in this building is materially effective in reducing the wind-induced vibrations. However, it is not as effective in mitigating remote seismic vibrations responses.