Abstract: With high proportion of renewable distributed power access to distribution network, the difficulty of reactive power and voltage regulation is increased greatly by its random output overlapped with load fluctuation. By considering dynamic reactive voltage regulation characteristics of renewable power sources such as wind power and photovoltaic, a dynamic partitioning real-time reactive power optimization model for distribution network is proposed. Based on the radial structure characteristics of distribution network and the reverse preliminary merging according to the nature of branch terminal nodes, the initial partition is performed with the maximum modularity function as the metric. The partition is adjusted according to the real-time operating status and the reactive reserve constraint to form the optimal partition scheme. Then the partitioning real-time voltage is regulated. Finally, the simulation analysis is carried out by MATLAB programming with the IEEE-33 node system as an example. The results show that the combination of intra-day real-time control and dynamic partitioning can effectively improve the speed and accuracy of system reactive voltage control.