According to the small current grounding fault line selection system for single-phase fault feature is not obvious due to difficulties even wrong line selection problem, proposed a small current grounding system fault line selection method based on empirical wavelet transform(EWT).The method uses empirical wavelet transform to advantages of adaptive segmentation to separate the different modes and the Fourier spectrum extraction AM-FM mode function, the modal component of zero sequence current of single-phase grounding fault in small current grounding system is extracted, and the low frequency modal component comprehensive correlation coefficient and high frequency energy of the zero sequence current value selection implementation fault line. Finally, the validity and superiority of the proposed method is verified in the Matlab simulation software.