The present disclosure provides a method for preparing a display panel, a display panel and a display device including the same. The method includes: providing a transparent substrate; and preparing a display structure and a protective film layer covering the display structure on the transparent substrate, in which the preparing the display structure includes: forming a pixel unit array and a lead metal layer on the transparent substrate; and forming a laser barrier layer on a surface of the lead metal layer away from the transparent substrate, in which an orthogonal projection of the laser barrier layer on the transparent substrate partially covers that of the lead metal layer on the transparent substrate.