The invention belongs to the technical field of power system dispatching, discloses a power system economic dispatching method based on distributed event driving, and provides a sufficient condition for realizing economic dispatching problem optimization under the communication topology. The whole network does not need a central processing unit, and each node only needs to exchange own state information with a neighbor node. By designing an event-driven function, each node in the network monitors its own state, and transmits its own state information to a neighbor node only when the event-driven function satisfies a certain condition. By designing a reasonable distributed event-driven algorithm, the optimal solution of the economic dispatch problem is obtained, and the Zeno phenomenon is eliminated. According to the invention, the communication cost is reduced and the system energy is saved. The method is suitable for economic dispatch, demand supply balance and other problems, lays atheoretical foundation for solving the problems, and enlarges the application range.