A method of manufacturing a display device includes forming a preliminary display panel including a light-emitting element on a substrate, and having a first dummy area at an outermost portion, attaching a preliminary support member under the preliminary display panel and having a second dummy area overlapping the first dummy area, removing an edge portion of the preliminary support member positioned around the second dummy area by irradiating a laser onto the preliminary support member, and forming a display panel and a support member having an end surface positioned on a virtual plane including an end surface of the display panel by irradiating another laser onto the preliminary support member, and by concurrently removing the first dummy area of the preliminary display panel and the second dummy area of the preliminary support member.