The pendulum tuned mass damper (PTMD) has been popular for vibration suppression due to its particular configuration form and frequency-tuning pattern. Based on the theoretical and numerical methods, a new prestressed TMD (PSTMD) has recently been presented which has better performances than the PTMD. To verify the improvement advantage and applicability comparatively, a comprehensive experimental study is carried out to investigate the vibration suppression of PSTMD in this paper. A wind turbine tower (WTT) with the lump-mass of the PSTMD can be represented by a two-degrees-of-freedom system, and its optimal design parameters can be analytically derived. Three test specimens, including the uncontrolled WTT, and the WTT with the PTMD or the PSTMD were tested in the laboratory with different equivalent wind and seismic loads via a shaking table. The presence of the PTMD or the PSTMD is noted changing only slightly the natural frequency and mode shape of the WTT, and the PSTMD exhibits the superior vibration suppression capability compared with the traditional PTMD.