Abstract: In view of the shortcomings of the existing time-frequency analysis methods such as wavelet transform and Hilbert-Huang transform in the analysis of measured signals of offshore wind turbines,this paper developed a short-time time-frequency analysis method based on the improved Prony method,and the correctness of the proposed method is verified by the measured data of the foundation of an offshore wind turbine and the offshore wind turbine structure. The practicability and feasibility of the proposed timefrequency analysis method are demonstrated by comparing with several existing time-frequency analysis methods.