The invention discloses a power line carrier system based on path cognition. The power line carrier system comprises a main carrier device, a plurality of secondary carrier devices and a plurality of backup path carrier devices, wherein the main carrier device is connected with a distribution and utilization system through a wire transmission network, and the backup path carrier devices are connected with the distribution and utilization system through a wireless communication network; the secondary carrier devices are used for sending backup authentications to the backup path carrier devices according to the status of a communication link, the backup path carrier devices are used for pushing and switching a backup path carrier device into a main carrier device from the backup path carrier devices according to the amount of received backup authentications for patch switching when an upstream channel of the main carrier device is invalid or the main carrier device is in fault. The invention further provides a networking method of the power line carrier system based on path cognition. The fusion of wireless communication and power line carrier communication is realized, and the robustness and stability of distribution and utilization station communication is improved.