The present disclosure provides a display panel, a display device including the display panel, and a method of manufacturing the display panel. The display panel includes a substrate; a pixel-defining layer disposed on the substrate, wherein the pixel-defining layer defines a plurality of sub-pixel regions arranged in rows and columns; and an organic light emitting element disposed in at least one of the plurality of sub-pixel regions, wherein a side of the pixel-defining layer away from the substrate is provided with a groove, the groove has a depth less than a thickness of the pixel-defining layer, and the groove is disposed between the organic light emitting elements that are adjacent to each other and emit light of different colors.