A display unit, a splicing screen, and a display device are provided. The display unit includes an edge area, and the edge area includes a mounting area and a side binding area. The display unit further includes: a first driving circuit layer located in the edge area and disposed on a side of the base substrate, a plurality of micro light-emitting elements disposed on the first driving circuit layer, and a binding part disposed in the side binding area and connected to the first driving circuit layer.