Abstract: In allusion to the diversity, complexity and uncertainty characteristics of third-party damage incidents, the third-party damage structural hierarchy assessment model is constructed according to the system engineering of "man-machine-environment-management". Then, a triangular fuzzy judgment matrix is constructed with expert's judgment information expressed by triangular fuzzy numbers. By use of fuzzy Analytical Hierarchy Process (AHP) to calculate weight, the general importance of each factor is obtained and ranked, and calculation method for risk factors of the third party to pipeline is given. The case study shows that fuzzy AHP can describe the fuzziness of export's judgment objectively and is simple and practical in calculation process. So, this approach can not only objectively assess the risk status of pipeline, but also is helpful to the improvement of pipeline risk management.