Tie device of building external scaffold

The utility model discloses a tying device of a building external scaffold, which comprises flat steel, the flat steel comprises a first section of steel body and a second section of steel body, the flat surface of the first section of steel body is horizontally arranged and pre-embedded in a building structure, the second section of steel body is exposed out of the building structure and can be folded on the building structure, and the end part of the second section of steel body is provided with a through hole; the second section of steel body is attached to a building structure when in a folded state, and the second section of steel body and the first section of steel body are located on the same horizontal line when in an unfolded state. One end of the transfer steel pipe is propped against the building structure, and the other end of the transfer steel pipe extends to the outer scaffold; and bolts on the pipe fasteners penetrate through the through holes in the second section of steel body, so that the f