The invention discloses a conductor lightning protection device which comprises a lightning protection device body and a conductor clamp holder. A first containing hole and a second containing hole are formed in the middle of the conductor clamp holder, a positioning bump is arranged between the first containing hole and the second containing hole, steel pricks are arranged inside the first containing hole and the second containing hole, a conductor penetrates the first containing hole and the second containing hole, a metal block is arranged on one side of the top of the conductor clamp holder, a discharge disk is arranged at the top of the metal block and connected with the metal block in a fastened manner by a screw, and an arc extinguishing cylinder is arranged at the top of the discharge disk. According to the conductor lightning protection device, arc extinguishing time is shortened by the arc extinguishing cylinder, burnout of the conductor is avoided by double voltage divisionof a discharge device and a grounding wire, the lightning protection effect of the device is further improved, the conductor is indirectly protected from long-time direct lightning strike, the conductor lightning protection device is good in durability, low in maintenance cost, high in reliability and long in service life, and a shield is omitted.