Abstract: Seismic fragility is an important part of seismic risk analysis, which can be adopted to predict the probabilities of structural damage induced by different levels of earthquakes. The fragility analysis provides an effective way for the seismic risk analysis and evaluation of earth-rockfill dams due to the dam performance with different degrees of damage under earthquakes. Considering the uncertainties of earth-rockfill dam material parameters and ground motion effect, a seismic fragility analysis method for earth-rockfill dams is proposed. Seismic response analysis is undertaken by using different peak accelerations of earthquakes. The combinations of material parameter samples are obtained by means of the method of orthogonal design. A fragility curve of the dam is proposed based on the relative settlement of the dam crest which serves as a seismic damage evaluation index. The seismic fragility analysis is applied in the Yunpeng Core Earth-rockfill Dam, and the risk probabilities with different seismic damages are obtained. This research is of great significance and applicable value for seismic risk assessment, seismic design, reinforcement and maintenance measures of earth-rockfill dams.