In view of the fuzziness and hierarchy of dam safety evaluation, the structural characteristics and failure mechanism of small earth-rockfill dams in China are analyzed to construct a safety evaluation index system considering the multi-criteria and multi-factors involved, based on which, a safety evaluation method is proposed combining analytical hierarchy process and fuzzy theory. According to this method, the weight of each index is calculated by the analytical hierarchy process and then modified by the fuzzy theory, so the membership value of each index in the evaluation system is obtained, and the evaluation result of the structure safety state is determined according to the maximum membership principle. In the study, the Kangmen Reservoir earth-rockfill dam in Yuhang District, Hangzhou City, Zhejiang Province is taken as a practical engineering example, and the proposed index system and evaluation method are applied to evaluate its structural safety level. Comparing the calculated evaluation results with the actual engineering situation, it can be found that the two are basically consistent, which in turn verifies the effectiveness of the index system and evaluation method. This study can provide a reference for the structural safety evaluation of earth-rockfill dams of small reservoirs.