Abstract: The conventional single-phase grounding fault diagnosis method for distribution lines mainly uses deep denoising autoencoders(DAE) to output fault location, which is easily affected by changes in sigmoid output, resulting in a high difference between the diagnostic section and the fault section. Therefore, this paper proposes a new single-phase grounding fault diagnosis method for distribution lines based on EEMD and wavelet threshold design. A denoising process for ground fault signals was generated using EEMD and wavelet thresholding, and a single-phase ground fault diagnosis algorithm for distribution lines was designed, thus completing the diagnosis of single-phase ground faults in distribution lines. The experimental results show that the diagnostic section of the designed EEMD wavelet threshold fault diagnosis method for single-phase grounding lines fits well with the fault section, proving that the diagnostic effect of the designed single-phase grounding fault diagnosis method is good, accurate, and has certain application value, making a certain contribution to improving the transmission and distribution safety of distribution lines.