Abstract: Aiming at the problems of unobvious fault characteristics, serious noise signal interference, and wrong and missing selection of single-phase grounding fault in the mine power supply system grounded by the arc suppression coil, a line selection method for single-phase ground fault based on Complementary Ensemble Empirical Model Decomposition (CEEMD) and autocorrelation threshold denoising was proposed. This method combines CEEMD with autocorrelation threshold denoising,and fault line selection is simultaneously completed according to the instantaneous am-plitude and instantaneous phase criteria.The system model was constructed using Real Time Digi-tal Simulator (RTDS),a large number of simulation tests were carried out under different fault point grounding resistance, fault initial phase angles, fault point locations and fault lines. The results show that this method, not affected by fault factors, has a better denoising effect than or-dinary denoising methods, and has high line selection accuracy and reliability. Therefore, this method is particularly suitable for single-phase grounding fault line selection of the mine power supply system grounded by the arc suppression coil.