The invention relates to transmission line monitoring technology, in particular to a transmission line state monitoring system based on a wireless electric private network and mesh topology. The system solves the problem that a reasonable network topology structure of an existing transmission line state monitoring network is not available. The transmission line state monitoring system based on the wireless electric private network and the mesh topology comprises a terminal part and a transmission medium part. The terminal part comprises FTUs, wireless network cameras, intelligent electric meters, wireless access points, a remote radio head, a wireless edge server, a network management server and an application server. The FTUs and the first wireless access point are connected in pairs through WiFi channels to form a mesh topology structure, the wireless network cameras and the second wireless access point are connected in pairs through WiFi channels to form a mesh topology structure, and the intelligent electric meters and the third wireless access point are connected in pairs through WiFi channels to form a mesh topology structure. The system is suitable for transmission lines.