Display panel, preparation method thereof and display device

The invention provides a display panel, a preparation method thereof and a display device, and belongs to the technical field of display. The display panel comprises a substrate, a switching electrode arranged on the substrate, a first flat layer arranged on the side, away from the substrate, of the switching electrode, a passivation layer arranged on the side, away from the substrate, of the first flat layer, and a plurality of light emitting devices arranged on the side, away from the first flat layer, of the passivation layer. A first electrode in the light-emitting device is electrically connected with the switching electrode through an overlapping via hole penetrating through the first flat layer; the passivation layer is provided with a plurality of first openings, the first openings and the lap-joint via holes are arranged in a one-to-one correspondence mode, and the edge contours of orthographic projections of the first openings on the substrate surround the edge contours of orthographic projections o