Abstract: An outdoor lightning protection power supply system comprises an AC distribution plant, an AC/DC rectifier and a backup battery, wherein a lightning protection system, a main earthing bar as well as a filter for absorbing AC load conducted interference is provided at the input terminal of the AC distribution plant, and there is provided an electrical box for accommodating them. Take the system lightning protection, the system earthing and the system filtering, as well as the system power supply into consolidated consideration, the present invention not only has the advantage of small volume and integration convenience, but also improves the reliability of the power supply system. Since the integration of the system is significantly improved, the number of the lightning protection module can be reduced, whereby reducing the system cost and saving the available space of the outdoor communication cabinet.