Electric fire monitoring system consists of Electric Fire Monitoring Host Machine, Residual Current Monitor and the system bus. The system exploits bus communication method. The residual current monitor and the detecting modules take separate configuration forms. They can accurately spot the fault loop location and monitor changes of the fault points and then sending off alarm in a centralized way, displaying, handling faults timely, recording faults of all kinds and processing experimental signals. The storage time is up to 12 months.