Abstract: Assessing the cumulative damage level of metal roof design within its expected service life is an important aspect of wind-resistant design. This paper proposes an estimation method for wind-induced fatigue damage throughout the entire service life of a metal roof system in typhoon-prone areas. This method uses wind tunnel test data and a model for wind speed and direction distribution based on Monte Carlo simulation of typhoons. By using the finite element numerical simulation method for load stress analysis, the stress-load relationship at the fatigue hot spot of the metal roof panel is extracted, and stress time series data is obtained. The stress cycle number is calculated by rain flow counting method. Then, according to the Goodman stress correction rule and the Miner fatigue linear cumulative damage theory, the cumulative fatigue damage of the metal roof system during its entire service life is calculated. The validity of the numerical simulation method is verified by dynamic physical pressure box testing using typhoon equivalent sequences. Based on this, the proposed method is applied to estimate the fatigue cumulative damage of a large-span cylindrical metal roof located in the southeast coastal area. The results show that the wind-induced fatigue damage of metal roofs throughout their service life is not only correlated with the distribution of wind pressure, but also with the distribution of extreme wind speeds and dominant wind directions in the region where the building is located. To evaluate the wind-induced fatigue damage throughout the service life, it is necessary to conduct a comprehensive analysis based on the wind tunnel test results as well as the wind speed and direction distribution model of the building location. For the high negative pressure areas in the roof corner and edge regions that are more prone to fatigue failure, the quantitative analysis of the effect of local densification of the corner and edge purlin spacing on wind-induced fatigue damage should be carried out.