The invention provides an electric power monitoring system having a fault position detection function. The electric power monitoring system is characterized by comprising a first signal emission source, a second signal emission source, a signal detector and a signal analyzer. According to the electric power monitoring system, a fault generation position can be determined by loading a predetermined-frequency pulse signal into an electrical signal of the electrical network and analyzing the loaded predetermined-frequency pulse signal, moreover, a magnetic field inductor is further added to the electric power monitoring system and is taken as equipment for assisting the system in determining the fault generation position, the electric power fault position is determined through monitoring change of the magnetic field generated in an electric power transmission process, through comprehensive analysis on determination made by the two, the found fault position can be more precise.