The invention provides a low-voltage cable theft prevention system, which belongs to the field of cable theft prevention devices. The low-voltage cable theft prevention system comprises integrated control units, tail-end transmitters and a backstage monitoring center, wherein the tail-end transmitters and the backstage monitoring center are all connected with the integrated control units; the backstage monitoring center comprises a backstage server, a UPS power supply, a Beidou timing device, a printer, a large screen and a GPRS module; the integrated control units are connected with a communication network; the backstage server is connected with the GPRS module and is accessed to the communication network through the GPRS module; the UPS power supply is connected with the power end of the backstage server; and the Beidou timing device, the printer and the large screen are all connected onto a communication interface of the backstage server. Thus, a theft prevention function can be provided when a street lamp is on or off.