There is provided an organic EL display device comprising: an underlying layer, including at least one layer formed of organic materials, formed on a substrate; organic EL elements formed thereon; and each leading electrode from the organic EL element for an electrical interconnection to an electrode of an interconnection object. In the display device, each connecting region is formed by removing the layers formed of organic materials, of the underlying layer, at a location of a thermocompression bonding for the electrical interconnection. This enables a reliable electrical interconnection between the leading electrode and the electrode of the interconnection object, thereby allowing a good display performance of each organic EL element to be kept.