The invention relates to a cable fixing device and a power distribution cabinet using the same. The cable fixing device comprises a base, and a first mounting beam and a second mounting beam arranged on the base side by side at intervals. The first mounting beam is provided with a first clamping structure. A second clamping structure is arranged on the second mounting beam. The mounting beams are movably mounted on the base through mounting structures so that the first and second mounting beams can achieve relative motion. The base is further provided with a driving mechanism used for driving the first mounting beam and the second mounting beam to move towards or backwards to adjust the distance therebetween. When cables are required to be uninstalled or installed, so long as the distance between the first mounting beam and the second mounting beam is adjusted by the driving mechanism, the respective mounting beams can move towards or backwards. Thus, when cables with different thicknesses are fixed, it can be guaranteed that the cable cannot deflected in the radial direction seriously and it can be avoided that axial traction is generated on the cables so as to cause damage to the cables or cable connectors.