Abstract: In order to effectively evaluate the risks of emergency repair of long-distance gas pipeline leakage, a dynamic AHP-based risk assessment model was established based on the Analytic Hierarchy process(AHP), with the risk indexes classified into five categories, and the updating algorithm of membership degree of various risk indexes was also described.Meanwhile, by analyzing the risks of emergency repair in the leakage accidents of gas pipelines, a dynamic AHP-based risk assessment evaluation index system was established, and the secondary indexes were classified. In addition, the dynamic evolution of risks faced in the overall construction period of emergency repair was analyzed with the dynamic AHP-based risk assessment model based on a leakage accident of Sichuan-East Gas Pipeline. The results show that: the changes of the risk indexes during emergency repair can cause the changes of the membership degree of the AHP underlying index and the index weight of each layer, which will further result in the risk change in the entire emergency repair process. Therefore, the model could effectively and dynamically evaluate the risks of emergency repair of gas pipeline leakage. Thus, the research results could provide basis for the emergency repair of natural gas pipeline leakage thereof.