The invention discloses a power line carrier centralized meter reading system based on low voltage user electro-network topology. The system comprises a first low-voltage power line carrier module and a second low-voltage power line carrier module, wherein the first low-voltage power line carrier module comprises a concentrator CPU, a first power carrier modem, a first zero phase identifier, a first buffer, a first low-pass filter, a first power amplifier, a first coupler, a third low-pass filter and a first amplifier; the second low-voltage power line carrier module comprises a watt hour meter data acquiring transmission CPU, a second power carrier modem, a second zero phase identifier, a second buffer, a second low-pass filter, a second power amplifier, a second coupler, a fourth low-pass filter and a first amplifier. The system is simple in structure, reasonable in design, high in automation degree, convenient to use and operate, and complete in function, the remote meter reading is realized, the manpower and material resource are saved, the work reliability is high, a use effect is good, and the popularization use is convenient.