Abstract: An evaluation Index System for the risk assessment is constructed. 12 indexes are defined, reflecting the natural condition, waterway situation, traffic density and management of a port. A risk evaluation model is constructed on the basis of an interval valued intuitionistic fuzzy set for the uncertainty, fuzziness and hesitancy of the raw information in nature. Basic evaluation information is integrated by means of the weighted arithmetic averaging operator. The weights of the indexes are defined according to the interval valued intuitionistic fuzzy entropy. The level of risk is determined according to the similarity between interval valued intuitionistic fuzzy sets. Empirical analysis is performed and satisfactory results are achieved.