The invention belongs to the technical field of hot-line work equipment, and particularly relates to an insulation vernier caliper for electric transmission line hot-line work. The insulation verniercaliper comprises a first insulation rod and a second insulation rod which are arranged in parallel, a first clamping plate is arranged at the upper end of the first insulation rod, and an upper limiting hoop and a lower limiting hoop are fixedly connected to the first insulation rod; a second clamping plate is arranged at the upper end of the second insulation rod and located below the first clamping plate, the second insulation rod is in slide connection with the upper limiting hoop and the lower limiting hoop, and scale lines are arranged on the outer surface of the second insulating rod. The insulation vernier caliper is manufactured based on the two insulation rods, the hoop and clamping plate design is matched, the distance between two arcing horns can be conveniently measured by a single person, remote hot-line measurement work is achieved, direct contact with high-voltage wire electrically charged equipment is avoided, safety in the measurement work process is improved, and convenient support is provided for electric transmission line hot-line overhaul work.