A mirror display apparatus includes a display unit, a thin film encapsulation layer, a plurality of mirror patterns, a protection layer and a refractive index matching layer. The display unit is disposed on a substrate. The thin film encapsulation layer extends continuously on a surface of the display unit. The mirror patterns are arranged on the thin film encapsulation layer. The protection layer is disposed on surfaces of the mirror patterns. The refractive index matching layer is interposed between the thin film encapsulation layer and the protection layer, and the refractive index matching layer fills regions between neighboring ones of the mirror patterns. A refractive index of the refractive index matching layer is less than a refractive index of the thin film encapsulation layer, and the refractive index of the refractive index matching layer is greater than a refractive index of the protection layer.