In order to analyze the dynamic behavior of flexible structures under wind load more realistically and reasonably, a vibration monitoring system is established for offshore wind tower structure, and on-site monitoring is conducted in the winter of 2018-2019.Based on a large number of measured data, the vibration characteristics of the flexible structure under wind load are clarified.Combined with numerical simulation, the rationality of the monitoring data is verified, and the vibration response of the structure under extreme wind conditions is predicted and analyzed.