When single-phase grounding fault occurs in power system transmission and distribution lines, it is difficult to extract fault feature information due to electromagnetic environment interference of electrical equipment, complex fault zero sequence current components and other reasons. Variational modal decomposition parameters are determined artificially, resulting in poor decomposition effect of zero sequence current, slow entropy operation and poor robustness, and low accuracy of subsequent line selection, a new zero-sequence current fault feature extraction method for single-phase grounding fault based on NGO-VMD-DE is proposed. Firstly, the adaptive decomposition of the zero-sequence current signal is realized through the northern goshawk optimization algorithm (NGO) optimization variational modal decomposition (VMD), and the selection criteria of the intrinsic mode functions component of the adaptive correlation coefficient are established. The effective IMF component is selected, and then the selected IMF component is reconstructed. Finally, the dispersion entropy (DE) of the reconstructed signal is calculated to extract the zero-sequence current fault characteristics of single-phase grounding fault, the proposed fault feature extraction method can more accurately and effectively characterize the zero-sequence current fault information of single-phase grounding fault lines by building a model for simulation experiments and comparing it with other characteristic entropy.