<p>Metal roofing systems are extensively used in long-span spatial structures due to their lightweight properties. However, their complex connection details make joints particularly susceptible to failure under strong winds, leading to wind uplift damage. In this study, a full-scale wind uplift resistance test was conducted on the prefabricated metal roofing system of Hangzhou Asian Games Esports Center, and found that the local damage and failure first occurred at the L-shaped connection joints connecting the roof panels and the secondary purlins. In order to comprehensively investigate the deformation and failure modes of the L-shaped joints under wind loading, a full process loading test was carried out on the joints. Simultaneously, a comparative study was conducted using the finite element method. The test and analysis indicate that the failure mode of the joint is that the weak cross-section of the L-shaped joint yields first, resulting in an out of plane “bulging” phenomenon and gradually separating the upper and lower parts of the joint. Quantitative results show that the average ultimate bearing capacity of the standard joint is 2.04 kN. The joint enters the plastic stage at approximately 1.0 kN, and severe buckling failure occurs when the load exceeds 1.3 kN. Based on these observations, this study develops a simplified mechanical model for calculating wind uplift capacity and proposes a practical design verification method for these L-shaped connection joints.</p>