The invention discloses a system for topology identification of electrical networks of a low-voltage distribution area. The system comprises a first communication unit embedded into a communication concentrator, a second communication unit embedded into a collector, a third communication unit embedded into an intelligent electric meter and a fourth communication unit embedded into an energy efficiency monitoring terminal, wherein the second communication unit is respectively connected to the first communication unit, the fourth communication unit and the third communication unit through a transmission module; and the transmission module comprises a low-voltage power line pulse modulation module and a 470 MHz wireless signal transmission module. Through utilization of a multi-network integration technology, the electric topology identification of supply networks is realized without changing a hardware structure, bidirectional quasi real-time communication between a power supply end and a power point can be realized, the first communication unit periodically and automatically analyzes a connection relation of the electrical networks of the area, the system can be integrated with an area electricity information acquisition device and complete electric topology data acquisition and uploading independently, and furthermore, the system has the characteristics of convenience for installation and high safety.