The invention provides a method for identifying key nodes of power network based on weighted power flow entropy and voltage stability, A technical field of identify key links of power network is disclosed, By acquiring basic data in the power grid system, the load rate and the weight corresponding to the load rate of the corresponding line of any node are calculated according to the active power,and the load rate is weighted and normalized, Then the load flow entropy of any node corresponding to the active power is calculated, and the weighted load flow entropy of any node is calculated according to the load rate and load flow entropy after weighted and normalized processing, and the voltage stability performance index is introduced, and the sum of the weighted load flow entropy and loadflow entropy after normalized processing is used as the basis for identifying the key nodes of the power network. Through the technical proposal of the invention, the limitation of the power flow entropy in identifying the key nodes of the power network is remedied, the accuracy and reliability of identifying the key nodes of the power network according to the weighted power flow entropy are improved, and the possibility of the cascading trip accident of the power network is reduced.