A material for sealing a display apparatus, the material having an improved mechanical strength and improved flowability, an organic light-emitting display apparatus including the material, and a method of manufacturing the organic light-emitting display apparatus are provided. The organic light-emitting display apparatus includes a lower substrate having a display area and a peripheral area around the display area; a display unit on the display area of the lower substrate; an upper substrate on the display unit and facing the lower substrate; and a sealing member on the peripheral area of the lower substrate to adhere the lower substrate and the upper substrate together, the sealing member including a glass powder, a first filler including a ceramic material, and a second filler including iron oxide.