Disclosed are a method and a device for locating a low-frequency oscillation disturbance source of an electric power system. The method includes: A, acquiring real-time operation data of electric generator power angles; B, subjecting the real-time operation data of the electric generator power angles to empirical mode decomposition so as to acquire a dominant oscillation mode IMF (intrinsic mode function); C, subjecting the dominant oscillation mode IMF to Hilbert transformation so as to acquire instantaneous amplitude values of the electric generator power angles; D, determining a disturbance source position according to the sudden change sequence of the instantaneous amplitude values of the electric generator power angles. By the method and the device for locating the low-frequency oscillation disturbance source of the electric power system, sudden change features of the electric generator power angle amplitude values in the initial oscillation phase can be acquired accurately, and thus, a generator set where the disturbance source is located can be recognized quickly.