The invention discloses a high-altitude maintenance trolley for a double-splitting transmission line, which comprises an upper trolley and a lower trolley, and is characterized in that the upper trolley is provided with upper pulleys and hung on an upper line, the lower trolley is provided with a lower pulley and hung on a lower line, the lower trolley is provided with a rotary seat, and the bottom surface of the lower trolley is further provided with a ling hanging device. The high-altitude maintenance trolley disclosed by the invention is simple in structure and convenient to be installed and removed, connection with the transmission line is firm and stable, safe production is guaranteed, the labor intensity is reduced, the operation time is shortened, and the labor efficiency is greatly improved.