The invention provides an OPGW-based power transmission line lightning flashover and non-flashover identification method. The method includes the following steps that: step 1, when a power transmission line is subjected to a lightning strike, lightning strike signals induced in an OPGW are collected; step 2, wavelet packet decomposition is performed on lightning strike signals of which the amplitude is larger than a threshold V1, and the energy proportion of each frequency band in a time-frequency domain is calculated; step 3, a selected low-frequency-band energy proportion, a selected high-frequency-band energy proportion and a threshold F1 are sequenced, if the sequence of the energy proportions satisfies a relation that low-frequency-band energy proportion>threshold F1>high-frequency-band energy proportion, the method shifts to step 4 for further judgment; step 4, the low-frequency bands of the signals are subjected to time-division processing, and whether lightning flashover occursis judged according to the trend of the change of the low-frequency-band energy proportion with time. With the OPGW-based power transmission line lightning flashover and non-flashover identificationmethod of the invention adopted, the lightning flashover situation of an entire line segment can be monitored, and a powerful basis can be provided for the development of line operation and maintenance work.