Abstract: The existing single-phase grounding fault detection technologies lack the ability of fault degree tracking and line selection during arc suppression process in distribution network. Making full use of the transient information during arc suppression process, the lumped parameter equivalent model considering line parameter asymmetry is established, the physical significance of attenuation characteristics of zero sequence voltage in arc suppression process is demonstrated, and a new fault detection method for distribution network considering fast arc suppression is proposed, which is highly sensitive to the detection of both low and high resistance grounding fault. Fault resistance measurement, fault degree tracking and fault line selection can be realized by observing the waveform of zero sequence voltage and current during the switching process of arc suppression full compensation in actual application. It is easy to operate and complete. The effectiveness of the method is verified by simulation experiments, which provides a new theoretical basis for ground fault detection of distribution network.