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The practical application of Hilbert-Huang transformation (HHT) method for structural modal parameters identification to a cantilever beam was investigated according to measured data of the acceleration response time histories for the cantilever beam under impulse excitation. The natural frequencies and modal damping ratios of the cantilever beam were identified using HHT method in combination with measured data. The identification results for the natural frequencies were compared with theoretical natural frequencies and those provided by the power spectrum method. Finally, the identification results for the modal damping ratios were compared with those provided by the half-power bandwidth method, the ZOOM FFT method and the time history decaying method, separately. The results demonstrate that HHT method is effective, robust and promising to structural parameters identification. Some problems of HHT method, such as it can not identify full modes and maybe identify “false modes”, are found.  