Consequences of dam-break are affected by many factors, which are of a certain degree of ambiguity. Influencing factors of dam-break consequences are summarized in this paper. At first, weights of influencing factors are determined by means of Analytic Hierarchy Process （AHP）, thereafter, the fuzzy hierarchy synthesis evaluation model for dam failure is developed. Finally, Qing Linjing reservoir located in Shenzhen of China is taken as a case. The fuzzy comprehensive evaluation for the risk analysis of dam-break and the risk grades of dam-break consequences are obtained. The results indicate that it is reasonable and valuable to evaluate the risk of dam-break by using fuzzy comprehensive evaluation.