Abstract: The performance level in existing studies on structural wind fragility was mostly well-defined, and its fuzziness was often ignored. Based on the finite element model and conventional performance levels, a wind fragility analysis method for the standing seam roof system at fuzzy performance levels is proposed, through the introduction of membership functions, to objectively describe its actual damage states under wind loading. Combined with a specific engineering example, established are the wind fragility curves of the standing seam roof system at fuzzy performance levels, and discussed are the effects of fuzziness factors and membership function forms on wind fragility. The analysis results show that: when the basic wind velocity is less than an intersection critical wind velocity, the fuzzy damage probability of the standing seam roof system is higher than or equal to the conventional damage probability, and conversely it is lower than or equal to the conventional damage probability. Under the same fuzziness factor, varying significantly is the effects of membership functions with various forms on structural wind fragility at conventional performance levels. The effect of the same membership function on structural wind fragility at conventional performance levels increases with the increasing fuzziness factor, i.e., wind fragility curves at fuzzy performance levels gradually deviate from those at conventional performance levels and tend to flatten out.