The invention discloses a connection box supporting frame in power cable laying construction. The supporting frame comprises a tubular inner cylinder, an upper supporting plate and a lower supporting plate. A counterweight is arranged below the tubular inner cylinder. The counterweight at the bottom of the tubular inner cylinder is provided with three fixation plates which are symmetrically arranged around the bottom end of the tubular inner cylinder. The fixation plates are connected with supporting legs through pins on the fixation plates. The tubular inner cylinder is slidably connected with a telescopic rod. The tubular inner cylinder and the telescopic rod are in clearance fit. An elastic movable sleeve is arranged between the inner cylinder and the telescopic rod. A fastening screw is arranged on the outer wall of the tubular inner cylinder. An angle adjustment head is arranged on the top of the telescopic rod. The angle adjustment head is screwed with a supporting column through a locking knob. The lower supporting plate is fixedly connected with the upper part of the supporting column. The lower supporting plate is fixedly connected with the upper supporting plate. A cable inlet is arranged between the upper supporting plate and the lower supporting plate. The upper supporting plate, the lower supporting plate and the cable inlet form a supporting structure. A cable fixing device is arranged on the supporting structure.