The utility model belongs to the transmission line field relates to a big drop topography overhead transmission line wire insulation support, including insulation support, strut type insulated column and a plurality of device that draws to one side, insulation support fixed mounting is on the slope, strut type insulated column bottom and insulation support's top fixed connection, the top of strut type insulated column hangs waits to support the wire, draw device one end and insulation support's top fixed connection to one side, draw the other end fixed mounting of device to be in to one side on the slope. The utility model provides a current big drop topography overhead transmission line have the technical problem that equipment trouble appears in potential safety hazard easily. The utility model discloses reliably there is convenient working space for the maintainer provides one with the help of overhead transmission line wire insulation support, solves the maintenance degree of difficulty because of the topography restriction brings.