A display apparatus includes a substrate having a display area in which an image is displayed and a peripheral area outside the display area; a thin film encapsulation layer at the display area, the thin film encapsulation layer including a first inorganic encapsulation layer, an organic encapsulation layer, and a second inorganic encapsulation layer that are stacked; a dam at the peripheral area; and an organic material detection part outside the dam, the organic material detection part including at least one detector. The first inorganic encapsulation layer and the second inorganic encapsulation layer extend from the display area to the peripheral area, and the first inorganic encapsulation layer has an opening that corresponds to at least a portion of the organic material detection part.