The invention provides a power distribution networksingle-phase grounding fault handling method based on a dual-mode function, and belongs to the technical field of powerdistribution automation. The technical scheme is mainly suitable for a delaylow-resistanceinputgrounding mode of a neutral point, and can be compatible with grounding modessuch as non-grounding of the neutral point, grounding of the neutral point through an arc suppression coil and grounding of the neutral point through low resistance. According to the scheme, a transientpower direction protection/grounding overcurrent protection dual-mode function is deployed for a first-stage section switch of a 10kV outgoing line of a transformer substation, thetransientpower direction protection/grounding overcurrent protection dual-mode function or a voltage-time type feeder automation function is deployed for a later-stage section switch, and when grounding faults occur, rapid handling of single-phase grounding faults is realizedby logic cooperation of all stages of switches.