Current leakage detecting device

The utility model relates to a circuit current leakage detecting device, which comprises a relay, a current mutual inductor and a microprocessor. The current mutual inductor is respectively connected with a power supply, a zero wire and a live wire through a sampling circuit; the current mutual inductor is sequentially connected with a gain amplifier, an analog-to-digital demodulator, a digital filter and a voltage effective value calculator in order; the voltage effective value calculator is respectively connected with a digital comparator and the microprocessor; the microprocessor is respectively connected with a threshold value register and the digital comparator; and a control signal output end of the microprocessor is connected with a control circuit of the relay. The current leakage detecting device has the advantages of being capable of rapidly and accurately judging leakage current, and visually displaying the amount of the leakage current, and simultaneously realizing current leakage protection.