Aiming at the problems of distribution network planning and power quality caused by the large-scale integration of distributed energy into the distribution network, the optimal operation of distribution network is studied. Starting from the impact of distributed generation on distribution network, this paper summarizes the distribution network reconfiguration technology, distributed generation location and capacity optimization, filter selection and location optimization, and analyzes and summarizes the modeling methods and constraints of distribution network optimal operation. Finally, it summarizes and prospects the optimal operation of distribution network.