An electrical circuit identification means is revealed. The electrical circuit identification device includes a signal generator connected directly to an AC power socket and a signal receiver set in a power control panel. The signal generator blocks a half cycle of sine waves and produces a short off-and-off signal at an interval. The signal receiver includes a signal sensor receiving signals from the signal generator and connected to both a control voltage divider and a signal strength switch for modulating and amplifying signals received by the control voltage divider, and a signal integration module that is connected to the signal strength switch and a microcontroller for outputting digital signals with different waveform. An identification system in the microcontroller cross checks the digital signals and the identification accuracy is determined according to the position of a light lit up in an indicator light module.