A method of manufacturing a flexible display apparatus includes sequentially forming a flexible substrate, a thin film transistor (TFT), an organic light-emitting diode (OLED) including a first electrode, an intermediate layer, and a second electrode, and a first attachment layer on a carrier substrate, sequentially forming a deposition layer and a second attachment layer on a sealing film, attaching the carrier substrate and the sealing film to each other such that the sealing film covers flexible substrate on the carrier substrate, sealing the first and second attachment layers, laminating the carrier substrate and the sealing film, and separating the sealing film and the flexible substrate from the carrier substrate.