The invention provides a resonant grounding system high resistance grounding fault transition resistance identification method. by using an over compensation role played by an arc suppression coil and in combination of advantages of transient signals, transient zero sequence current in a fault point is calculated and obtained by using transient zero sequence voltage of a bus and a fault line and the transient zero sequence current of any perfect feeder line, and thus, the transition resistance value is calculated. In comparison with the prior art, the zero sequence voltage of the system and the zero sequence current signal of each outgoing line are only needed, three-phase voltage and three-phase current signals are not needed, realization of the present small current grounding fault line selection device is facilitated, and influences of TV/TA transmission errors and imbalance do not exist. The technology has a wide practical application value in helping an operator with accuracy system analysis, line selection on high resistance grounding fault, positioning and distance measurement, and has important significance and important theoretical value in improving the action performance of a protective device against the transition resistance.