The invention discloses an optical cable tightener, and relates to the technical field of overhead line regulation devices. The optical cable tightener comprises a connecting frame and a rope sheave arranged on the connecting frame, a fixation hook is arranged at the left end of the connecting frame, a wrench is arranged on the side portion of the connecting portion, a steel rope winds the rope sheave, and a traction hook is fixed to the free end of the steel rope to be connected with a preformed armor rod strain clamp in a clamped mode. The optical cable tightener has the advantages of being simple in structure, light in weight, small in size, convenient to carry and use, free of damage to an optical cable, capable of regulating the sag degree of the optical cable to meet a required standard with time and labor saved, reducing labor intensity, improving working efficiency, and being suitable for mobility of optical cable erection and the diversity of operation environments.