Disclosed is an optical-cable-fixing support including a fixing piece and a fixing branch box. The fixing piece is arranged at the bottom part of the fixing branch box. The fixing piece includes a U-shaped clamping piece and a rotating support. A customization U rail part is installed on a machine cabinet of the optical-cable-fixing support and the customization U rail part is fixed on the machine cabinet through nuts and a nut backing strip. The U-shaped clamping piece is slid to an appropriate position and locked through the nuts. The rotating support is a symmetrical support with the middle part being riveted. One side of the rotating support is connected with the back of the U-shaped clamping piece and the other end of the rotating support is connected with the back of the fixing branch box. An insulating layer is arranged between the U-shaped clamping piece and the rotating support. The optical-cable-fixing support is applicable to an industrial site and has functions of protecting and fixing an optical cable and particularly, high-voltage protection measures are arranged in the support so that an optical-fiber fault probability resulted from poor optical-fiber fixing and protection is reduced effectively.