Abstract: Aiming at the current situation that the secondary voltage partition fails to achieve dynamic non-interference adjustment, an adaptive dynamic partitioning and pilot node selection method with real-time grid operating conditions was proposed based on the voltage/reactive sensitivity and modularity function. With each reactive power source as the partition center, each load node was mapped to the corresponding reactive power source according to the voltage/reactive sensitivity; an improved modularity function considering reactive power margin was constructed and used as a measure index to merge regions and automatically form the optimal partition. The anti-interference index of other regional nodes to the pilot nodes was introduced, and combined together with the observability and controllability index of the pilot nodes in the region to determine the selection scheme of the pilot nodes. The partition results were evaluated and verified based on reactive power source control sensitivity, reactive power margin and the observability of the pilot node. Finally, the IEEE-39 node system was taken as an example to verify the effectiveness and superiority of the proposed method.