Disclosed are a manufacturing method of a display panel, a display panel and a display device. The manufacturing method includes the following steps: providing a base substrate; forming a planarization layer on a side of the base substrate; forming a first film layer on a side of the planarization layer facing away from the base substrate; forming an anode via penetrating through the first film layer and the planarization layer; forming an anode layer on a side of the first film layer facing away from the base substrate; patterning the anode layer to form a first opening on the anode layer; and after patterning the anode layer, patterning the first film layer to form a second opening on the first film layer. A material of the first film layer includes a non-metallic material.