The utility model belongs to the technical field of junction boxes, and particularly relates to a waterproof device of an
electrical junction box, which comprises a
junction box, a sealing cover is arranged at the top of the
junction box, a positioning
assembly for limiting the sealing cover is arranged on the
junction box, and a clamping groove is fixedly arranged in the junction box. A frame corresponding to the clamping groove is fixedly installed at the bottom of the sealing cover, the bottom end of the frame extends into the clamping groove, and an air bag is arranged in the frame in a surrounding mode. According to the waterproof device of the
electrical junction box, the sealing performance of the waterproof device of the
electrical junction box can be improved through the installed frame and the installed air bag, the frame extends into the clamping groove, the connecting plate moves, the connecting plate pushes the compression block to move through the driving rod when moving, and the compression block moves to extrude air in the compression groove; and extruded air flows into the air bag through the connecting
pipe, so that the volume of the air bag is expanded, the sealing performance of a gap between the junction box and the sealing cover can be improved, the waterproof effect is improved, and the practicability of the waterproof device of the electrical junction box is improved.