The invention discloses a method for evaluating voltage interacting degrees among different levels along with the connection of an extra-high voltage DC in a hierarchical manner, and belongs to the technical field of operation and control in a power system. According to the invention, the method includes the following steps: based on the characteristics of the extra-high voltage DC connecting to an AC grid in a hierarchical way, establishing an equivalence model of an AC/DC system, at the same time based on the operation of the DC system and the operation of the AC system, establishing a flow constraint equation of the equivalence model, then deriving a reduction jacobian matrix of the flow constraint equation at an operating point, finally resolving an inverse matrix of the reduction jacobian matrix, acquiring elements of the jacobian matrix, and conducting corresponding calculation and processing to obtain voltage interacting factor of the 500kV level and the 1000kV level. According to the invention, the method can provide guidance for reactive configuration and reactive optimization of the connection of the extra-high voltage DC to the engineering 500kV level and the 1000kV level in a hierarchical manner.