The invention discloses a method for decomposing a non-invasive electric power load, and belongs to the technical field of electric power load monitoring. The method for decomposing the non-invasive electric power load comprises the steps of 1, collecting and inputting power consumption data of a standard industrial user, thereby obtaining an electric load signal waveform diagram of the industrialuser; 2, carrying out wavelet packet decomposition on the electric load signal waveform diagram of the industrial user; and 3, carrying out frequency spectrum conversion and decomposition on a low-frequency signal by fast Fourier transform. According to the method for decomposing the non-invasive electric power load, the wavelet packet decomposition (WPD) is combined with the fast Fourier transform (FFT) to carry out signal decomposition and frequency spectrum conversion on load information of the industrial user so as to obtain operation conditions and cycles of production processes of the industrial user; and relevant production capacity and yield are calculated in combination with the kilowatt-hour production capacity of the processes.