The invention belongs to the technical field of electrical engineering, and particularly relates to the Hilbert-Hung and the MEMD. The method comprises the steps of: uploading measurement informationof a transmission circuit and a bus node in an actual power grid to a data concentration unit by adopting the real-time data collection function of a PWU device, and extracting key information for mode identification. The method provided by the invention can achieve rapid, accurate and efficient identification for the dominant oscillation mode of the electric power system based on the actually measured information of the PWU, the Teager energy operator criterion is introduced to screen out the key IMF components containing the dominant oscillation mode so as to avoid the influence of noise components in PMU actual measurement data on an identification result; and moreover, the oscillation frequency and the damping ratio change curve are observed by adopting the features of the Hilbert-Hungto track the instant oscillation frequency and the instant damping ratio of the dominant oscillation mode to obtain the mean value of the instant oscillation parameters and estimate the oscillation parameters of the dominant oscillation mode.