The invention discloses an electric power system operation state coordinated optimization method comprising the steps that the target function of electric power system cascading failure is determined; the constraint conditions of the target function are set; a cascading failure risk coordinated optimization model is established according to the target function and the constraint conditions; the optimal target function value is determined by adopting the cascading failure risk coordinated optimization model; the corresponding operation of the optimal target function value is determined; and the electric power system is adjusted according to the operation. Cascading failure simulation is performed by using the cascading failure model and risk assessment is performed, and the obtained risk indictor has clear physical meaning, i.e. loss load or economic loss so that the method has higher practicality in comparison with the conventional method based on a severity function. Besides, the function of multistage cascading failure correlation is used as the risk constraint so as to further reflect the development characteristics and risk distribution of the actual multistage cascading failure, and thus the accuracy is higher.