A flexible organic light-emitting display device and a method of manufacturing the flexible organic light-emitting display device are provided. The flexible organic light-emitting display device comprises a lower flexible substrate assembly and an upper flexible substrate assembly that are bonded by a bonding layer. The lower flexible substrate assembly includes a first flexible substrate, a thin film transistor formed on the first flexible substrate, a white organic light-emitting element formed on the thin film transistor, and an encapsulation layer formed on the white organic light-emitting element. The upper flexible substrate assembly comprises a second flexible substrate, an interlayer and a touch sensing unit formed on the interlayer layer. The interlayer may be at least one of a color filter layer, a transparent resin layer, an insulating film layer and a second flexible substrate.