An organic EL display device which can prolong a lifetime by suppressing a growth of black spots when the display device is operated for a long time can be realized. An element substrate on which organic EL layers are formed is hermetically adhered to a sealing substrate on which a desiccant is mounted by way of a sealing portion. The element substrate and the sealing substrate are curved outwardly. Particularly, by curving the element substrate outwardly, a growth of black points can be prevented when the organic EL display device is operated for a long time. Accordingly, a lifetime of the organic EL display device can be remarkably prolonged.