Failure to detect and evaluate damage situation of engineering structures can result in disastrous accidents. It is greatly significant to identify damage degree of the structures in normal service, evaluate the safety of damaged structure, and predict the residual reliability accurately. In order to overcome the deficiency of uncertain factors in current evaluation process, a multi-level fuzzy synthesized evaluation method is proposed, in which Analytic Hierarchy Process is utilized to establish the evaluation index system and determine weight aggregates. The method can analyze the damage information quantitatively and present structural damage grade effectively, so as to provide the administrators with valid information, which could be valuable in deciding whether to maintain or rebuild them. An engineering example provided here demonstrates that the evaluation method is simple in performance and reasonable in results.