A display device and a method of manufacturing the display device being capable of substantially preventing infiltration of moisture or oxygen (O2) into a quantum dot layer by scribe cutting a display panel including quantum dots and then thermally curing a cell edge portion with laser for sealing the quantum dot layer in a manufacturing process are provided. The display device includes: a glass plate; a first passivation layer disposed on the glass plate; a wavelength conversion layer disposed on the first passivation layer; a second passivation layer disposed on the wavelength conversion layer; an optical sheet disposed on the second passivation layer; a display panel disposed on the optical sheet; and a laser trim portion extending along edges of the first passivation layer, the wavelength conversion layer, and the second passivation layer.