The red and black mechanism of the process of dynamic change in the graph， network topology and equipment life cycle in the distribution network is proposed to cope with the frequent change of the model and topology for distribution networks in China. The concept and relation of the graph state， topology model， equipment operation state in red and black mechanism is described. The realization principle of red and black mechanism is expounded with respect to the data model， data entity， graph version， network topology and application realization. The closed-loop flow control between GIS and DMS based on the red and black mechanism is implemented in Nanjing Power Supply Company. The application results show that the red and black mechanism truly reflects the process of the dynamic distribution network change while satisfying the day-to-day requirements of the dispatchers.