The invention discloses a high-voltage overhead transmission line icing diagnosis method. The high-voltage overhead transmission line icing diagnosis method uses voltage current on two sides of a power transmission line as a signal source including steady state data at two ends of the power transmission line, system transient state and line self failure data, and a reference voltage and current data set reflecting icing parameter features is dynamically generated in a self-adaptive mode. Detection data and generalized correlation coefficients of the reference data set serve as judgment standard, and the icing area and severity degree of the power transmission line are diagnosed according to the generalized correlation coefficients. According to different reference data, the diagnosis methods include a single positive-sequence diagnosis method and a total-order redundancy diagnosis method. In addition, a fault component network detection line icing method is adopted, the icing detection flexibility is ensured in principle, and the accuracy and reliability of line icing detection are improved. A diagnosis result is obtained through centralized comparison of the reference data and conforms to a maximum membership degree principle and a stable allocation theory, and the accuracy and reliability of the diagnosis method are ensured theoretically.