The invention relates to the field of building construction, and especially discloses a construction site electric wire hanging device. The construction site electric wire hanging device comprises a main plate and a right-angle bending plate which are fixed together, and is characterized in that the main plate is parallel to a surface of the right-angle bending plate, a rotating plate is hinged between the main plate and the right-angle bending plate, the outer end of the rotating plate is hinged with a hook, the hook is provided with an insulating sheath in a sleeved manner, the inner end of the rotating plate is arc-shaped, the main plate is hinged with a fixing plate, the end, which is close to the main plate, of the fixing plate is an arc-shaped groove, and the fixing plate is connected with the other surface of the right-angle bending plate through a fastener. The construction site electric wire hanging device is firstly fixed on a reinforced steel bar through coordination of the main plate, the right-angle bending plate and the fixing plate, then an electric wire is hung on the hook, an anti-slip stripe at the inner end of the hook is contacted with the reinforced steel bar, the inner end of the hook is tightly contacted with the reinforced steel bar because of a gravity action of the electric wire, the electric wire is hung on the hook, and potential safety hazards brought about by dragging the electric wire on the ground are avoided.