The application relates to the electric power fault identification technology field, in particular to a distribution network arc grounding fault identification method. A conventional power distribution network usually weakens the arc overvoltage harm in an operation manner of grounding an arc suppression coil or a small resistor, but the further processing is not carried out aiming at an arc grounding fault. The distribution network arc grounding fault identification method provided by the application comprises the steps of obtaining the fault phase voltage and zero sequence current waveform data of the fault, and determining the fault generation moment; calculating a fault phase voltage and current singular integral feature sequence T after the generation of the fault; gathering the mutation number of times of the singular integral feature sequence T within a preset period of time when the fault is generated, and determining the type of the fault. By calculating the current and voltage numerical values at the normal operation of a line via the waveform data before the generation of the fault, analyzing and processing a voltage and a zero sequence current during an arc discharge process after the fault is generated, extracting the singular integral feature sequence to describe an arc discharge phenomenon during a fault process, and gathering the generation frequency, the type of the fault is identified.