Abstract: A hanging device for frames comprising a supporting assembly that is mounted to a vertical wall and a hanging assembly that is rigidly mounted to the back of a frame or other object to be hung. The hanging assembly has front and rear walls separated by an upper wall. The upper wall is removably mounted to the supporting assembly. The supporting assembly has a tubular shape with a rectangular cross-section. The supporting assembly includes a straight edge against which the straight upper wall of the hanging assembly rests ensuring that the frame will conform to the same orientation, typically horizontal, of the straight edge. A leveling device is mounted to the supporting assembly to facilitate the determination of the position of the latter.