Power grid fault positioning system

The invention provides a power grid fault positioning system and a method. The system comprises a fault indicator which is arranged on a branch line of a power grid and sends a fault signal comprising the branch line information when detecting preset fault current on the branch line, a communication terminal which is connected with the fault indicator, receives the fault signal sent by the fault indicator and sends the fault signal, and a fault positioning module which receives the fault signal and determines the position of a fault point according to the fault signal. According to the system, people do not need to use a piecewise power outage method to query the fault point, and thus the stability of power supply of the power grid is improved.