The invention discloses an optimized dispatching method for improving the load rate of a power distribution network, aiming at improving the load rate. The method comprises the following steps of building a power supply model of a power distribution network based on an index system of the power distribution network for evaluating the power supply capability, deriving a method for computing the load rate of the power distribution network, and adopting corresponding measures from an optimized running mode under the constraint conditions that the N-1 running mode is met, the power supply reliability is not lower than 99.99%, and the voltage qualified rate is not lower than 99.99% to improve the whole load capacity of the power distribution network. According to the optimized dispatching method for improving the load rate of the power distribution network disclosed by the invention, the phenomena that the whole load rate is not high and is not balanced commonly existed in the domestic power distribution network can be solved, and the power supply reliability and the voltage qualified rate can be improved as well.