The invention discloses an economic dispatching parallel calculation method for a large-scale power network, which can optimize the calculation efficiency of online economic dispatching. On the basisof dividing the power network into regions by grid division traversal algorithm, the result of economic dispatching can be calculated by parallel computation, and the sub-region coordination can be carried out again according to the result, and the new divided region can be formed, and then the parallel computation and iteration can be carried out again. A large-scale power network topology regionis divided according to a power network division traversal algorithm, so that that large-scale power network region is decomposed into several sub-regions, and the large-scale and complex economic dispatch problem is converted into solving a plurality of small-scale linear programming models. The invention calculates the economic dispatching result of each sub-region separately by the algorithm of the parallel calculation, so that the calculation of a plurality of models can run at the same time, the calculation amount is reduced, the calculation time is saved, the calculation cost is reduced, and the calculation efficiency is improved.