An organic light emitting diode display is provided including: a substrate including a display area and a non-display area positioned at a circumference of the display area; a thin film transistor formed on the substrate; a first electrode formed on the thin film transistor and electrically connected to the thin film transistor; a pixel definition layer formed on the first electrode and defining a pixel area; and an emission layer formed on the first electrode and contacting the first electrode in the pixel area, wherein the display area is divided into a first region, and a second region including a remainder of the display area except for the first region, and a cross-sectional area ratio of the pixel definition layer that a cross-section of the pixel definition layer occupies for a unit pixel is different in the first region and the second region.