Abstract: This study proposes a performance-informed method for assessing multi-hazard coupling effects of monopile-supported wind turbine towers. This methodology integrates multi-hazard hazard modeling, wind-induced structural fatigue, multi-hazard fragility and failure risk, which is defined as performance-based multi-hazard engineering representing the main contribution of this current study. First, based on measured data from 1970 to 2017, a seismic hazard model, a copula-based joint probability model of wind speed and direction, and a joint probability model of seismic and wind events are established. Second, taking the NREL-5MW wind turbine tower structure as an example, a wind-induced structural fatigue damage analysis considering wind direction effects is conducted. The study indicates that wind direction significantly affects the cumulative wind-induced fatigue damage of the structure, and that the fatigue life is less than the design service life of the structure under the wind direction ranging from 0° to 150°. Third, the structural fragility corresponding to different limit states is computed for three hazard scenarios of an individual earthquake, of an individual wind and a simultaneous wind and, of a seismic action. The numerical results indicate that simultaneous wind and seismic action significantly amplifies structural responses, and that the associated fragility is not a simple superposition of individual hazards. Finally, the annual failure risk is computed by convolving the multi-hazard hazard with structural fragility. The study finds that for the damage states of shutdown and long-term shutdown, the contribution of wind load alone to the annual failure risk is approximately 50%, while that the simultaneous action of wind and earthquake accounts for about 30%. For the damage states of long-term shutdown and collapse, the contribution of seismic action alone exceeds 60%. The performance-informed multi-hazard evaluation methodology presented can provide a theoretical basis for the uniform-risk multi-hazard design of wind turbine tower structures.