This paper presents a probabilistic damage analysis method to generate seismic fragility curves of structures. Uncertainties in earthquake and structure are quantified by evaluating uncertainties in parameters that define the earthquake-structure system. The uncertainty in each parameter is characterized by several representative values that are selected considering the uncertainty range of the parameter and its use in engineering practices. Samples of structures and earthquake motions are constructed from the combination of these representative values, then the Latin hypercube sampling technique is used to construct the samples of earthquake-structure system. For each sample, the nonlinear seismic analysis is performed to produce response data, which are then statistically analyzed. On the other hand, five limit states representing various degrees of structural damage are defined and the statistics of the structural capacity corresponding to each limit state can be established. The fragility curve is generated by evaluating the limit state probabilities at different levels of peak ground acceleration. For illustration, the fragility curves of a five-story shear wall building are constructed. © ASCE.