Disclosed is an extra-high-voltage transformer station optical cable terminal voltage-limiting apparatus. The apparatus comprises a voltage limiter, the two ends of the voltage limiter are respectively connected with an upper-end connecting plate and a lower-end connecting plate, the upper-end connecting plate is connected with a voltage cable upper cover, the lower-end connecting plate is connected with a lengthening column, the upper end of an insulation spacer support is connected with a voltage cable lower cover, the lower end of an insulation spacer plate is connected with the lengthening column, and the lower end of the lengthening column is connected with a hold hoop. The extra-high-voltage transformer station optical cable terminal voltage-limiting apparatus improves the safe operation rate of a 1000KV extra-high-voltage transformer station OPGW terminal leading-down cable, eliminates equipment hidden risks of an OPGW optical cable line in operation, reduces power-failure maintenance work, improves the safe operation rate of an extra-high-voltage power grid and decreases the operation cost of a power grid enterprise.