An organic light-emitting display apparatus including a substrate having a display area and a peripheral area; a TFT in the display area; an organic insulating layer on the TFT; an OLED that includes a pixel electrode electrically connected to the TFT, an emission layer on the pixel electrode, and a counter electrode facing the pixel electrode with the emission layer therebetween; a pixel-defining layer on the organic insulating layer and having an opening overlying the pixel electrode; a first dam in the peripheral area; a second dam in the peripheral area to surround an outer periphery of the first dam; a metal-containing layer covering the first dam and including a same material as the pixel electrode; and a thin-film encapsulator on the substrate to cover the OLED and including a first and second inorganic films, and an organic film between the first and second inorganic films.