The invention discloses a recursive cutting type zone control method of reactive voltage, belongs to the field of electrical power system safety analysis and operation control, and particularly relates to a node coupling relationship analysis and reactive voltage zone control method of an electrical power system. The problem that when the zone control method of the reactive voltage is applied to interconnected grids with non-uniform grid structures, the adaptability is poor is solved. The method comprises the steps as follows: a power supply node coupling relationship matrix and a voltage control sensitivity matrix HLG of power supply nodes to load nodes are calculated firstly; power supply nodes in a to-be-cut zone is divided into two groups, wherein one group has an intra-group coupling degree lager than Gamma (k), and the other group has an inter-group coupling degree smaller than Gamma (k); load nodes in the to-be-cut zone are merged into node sets of corresponding power supply nodes; whether sub-zones of the node sets meet the termination conditions of the sub-zones is judged, and if the termination conditions are met, the partition of nodes and sets is ended; then grid voltage of the zones is controlled, and operation control of the grid voltage of the zones is completed; otherwise, partition is performed continuously. The recursive cutting type zone control method of the reactive voltage is applicable to electrical power system safety analysis and operation control.