The invention relates to the power transmission line monitoring technology, in particular to a power transmission line video and environmental monitoring system based on ring topology structures, solving the problem that existing power transmission line video and environmental monitoring network is short of reasonable ring topology structures. The power transmission line video and environmental monitoring system based on the ring topology structures comprises a terminal unit and a transmission medium unit. The terminal unit comprises wired network cameras, wired temperature sensors, tower inclination monitors, wireless access units, a remote radio unit, a wireless edge server, a network management server and an application server. The wired network cameras and the first wireless access unit are connected end to end through a power line to form one ring topology structure; the wired temperature sensors and the second wireless access unit are connected end to end through a power line to form another ring topology structure; and the tower inclination monitors and the third wireless access unit are connected end to end through a power line to form the other ring topology structure. The video and environmental monitoring system is applicable to power transmission lines.