Display panel, preparation method thereof and display device

The invention provides a display panel, a preparation method thereof and a display device. The preparation method of the display panel comprises the steps that a thin film transistor is formed on a substrate, and the thin film transistor comprises a grid electrode, a first electrode and a second electrode; forming an insulating layer and a conductive connecting part penetrating through the insulating layer on one side, far away from the substrate, of the thin film transistor; the surface, away from the substrate, of the conductive connecting part is flush with the surface, away from the substrate, of the insulating layer. Forming a light-emitting element on one side, far away from the substrate, of the conductive connecting part; the light-emitting element comprises a first electrode and a second electrode located on the side, away from the substrate, of the first electrode. The first electrode is in direct contact with the surface, away from the substrate, of the conductive connecting part, and the orthograp