A support substrate having the same size as a device substrate provided with alignment marks is disposed opposite to and adhered to the back side of the device substrate. At least the face side of the device substrate on the support substrate is cut at division lines along a functional region. An organic film is formed on the functional region of the device substrate thus cut. The support substrate is cut along the functional region of the device substrate, thereby removing peripheral portions of the support substrate and the device substrate, to form a display panel. Positioning of the substrate relative to a manufacturing apparatus for each step can be performed with high accuracy, in the manufacturing process including a step of cutting the substrate to a smaller size in the course of manufacture.