Аннотация:With analysis of the typical development process of cascading failures, a new cascading failures prediction method is proposed basing on self-organized criticality. Firstly, according to the overall operation situation of power system, the features of self-organized criticality, which has non-uniform system structure and non-uniform state, is analyzed. Then an evaluation indicator to estimate self-organized criticality line on the whole is proposed. Secondly, focusing on changes of flow and structure after each level of cascading failures, self-organized criticality line cluster is screened. Combining with comprehensive margin index which reflects changes of state and structure after power failure, cascading failure in a self-organized criticality lines cluster is forecasted according to comprehensive margin index. Lastly, in consideration of the actual operation of the power grid, weather factor is considered to build an impeccable model of cascading failures in which the feasibility and validity of the algorithm is analyzed by using IEEE30 bus system.