The invention discloses a method for comprehensive online prevention and control decision making, and the method meets the requirements for the constrains of the multiple types of safety and stability, and belongs to the prevention and control technical field of safety and stability in electric power systems. The method, directed to the features of large power grids, such as intertwining of multiple types of safety and stability problems and insufficient time for online decision making, proposes control performance indexes of adjustment measurements of electric generators, loads and capacitive reactance devices for a total of 11 types of safety and stability, such as transient safety and stability, dynamic safety and stability and static safety and stability, and independently lining up and selecting different types of measurements based on a comprehensive performance index of safety and stability, and enumerating and combining measurements selected, and applying a cluster computing platform to implement a quantitative estimation of the safety and stability of the measurements enumerated and combined; defining the calculation of the comprehensive decision-making of the transient safety and stability and the dynamic safety and stability as a phase, defining the calculation of the decision-making of the static safety and stability as an independent phase, optimizing the solution of the transient safety and stability and dynamic safety and stability problems, and adopting a cyclical iteration calculation scheme. The method can implement a method for fast and optimized online prevention and control decision making taking the constrains of multiple types of safety and stability into consideration.