An organic light-emitting display device and a method of manufacturing the same are provided. An organic light-emitting display device includes: a light-emitting element on a substrate, and an encapsulation unit on the light-emitting element, the encapsulation unit including: a plurality of inorganic encapsulation layers, at least one of the inorganic encapsulation layers including: a plurality of inorganic insulation layers, and at least one element encapsulation layer between the inorganic insulation layers, the at least one element encapsulation layer including at least one of: a hydrophobic element and an inert element, and at least one organic encapsulation layer between the inorganic encapsulation layers.