The invention discloses an adjustable cable paying-off support, and relates to the field of system operation tools. The adjustable cable pay-off support includes a shaft lever and a support body in mirror symmetry with the shaft lever, wherein the shaft lever is placed on the support body that includes two pedestals, a first support rod and a second support rod, one end of the first support rod is hinged to one end of the second support rod, each pedestal is connected to a lead screw through a first nut seat and a second nut seat, the left end of each pedestal is hinged to the other end of the first support rod, a first nut is arranged at the right end of the lead screw, the first nut seat connected to the first nut is hinged to the other end of the second support rod. According to the adjustable cable paying-off support, the lead screw, the first support rod and the second support rod constitute an isosceles triangle, the width of the second support rod is adjusted through rotating the left end of the lead screw, namely the width of the base of the isosceles triangle is adjusted and the purpose of adjusting the height of the shaft lever on the support is achieved; and therefore, the cable paying-off support can be applied to various cable reels with different diameters, thus reducing labor intensity, improving work efficiency, and being simple in structure and convenient to operate and disassemble, store and transport.