The invention provides a single-phase arc-grounding simulation device for a power distribution network. The single-phase arc-grounding simulation device comprises a 380V equivalent power distribution network, an arc current generator and a high-voltage switch, wherein the 380V equivalent power distribution network comprises a three-phase isolation transformer, a network ground capacitor and a single-phase step-up transformer; the 380V equivalent power distribution network improves a 380V power-frequency voltage to 10kV; the arc current generator generates an arc current at the 10kV voltage; the arc current generator comprises a current input terminal, a fuse and a current output terminal; one end of a secondary winding of the single-phase step-up transformer is grounded and the other end is connected with the current input terminal; the current input terminal is fixedly connected with one end of the fuse; the other end of the fuse is suspended; a distance which is about 1-3mm is kept between the fuse and the current output terminal; and the current output terminal is connected with the high-voltage switch and then is grounded. The single-phase arc-grounding simulation device can simulate an arc-grounding fault of the power distribution network under the condition of a 380V power supply, greatly reduces the power supply capacity and the equipment cost of an experiment platform and also reduces the safety risk of the experiment work.