The utility model discloses a high -voltage electrical equipment earth current on -line monitoring device, the device is big current rush counting assembly and current detection device with high -voltage electrical equipment ground end electrical connection including the while, big current rush counting assembly includes electrical connection's energy storage mutual -inductor and heavy current signal acquisition mutual -inductor, and wherein energy storage mutual -inductor and high -voltage electrical equipment ground end electrical connection have connect a rectifier module and energy storage module in proper order on the energy storage mutual -inductor, have connect trigger module, count module and display module on heavy current signal acquisition mutual -inductor in proper order, the energy storage module is connected electrical connection between trigger module and the energy storage module with the count module again, current detection device includes the current detection mutual -inductor of holding electrical connection with the high -voltage electrical equipment ground, has connect the 2nd rectifier module and gauge outfit display module on the current detection mutual -inductor in proper order. The utility model discloses passive, no internal resistance, high accuracy.