PURPOSE: An organic electroluminescent device is provided to improve luminous efficiency by forming multiple convex patterns on a substrate and changing the substrate incident angle of the light emitted from an organic light-emitting layer. CONSTITUTION: A substrate(100) has multiple convex patterns on one side. A planarization layer(200) is formed on the multiple convex patterns of the substrate. A first electrode(300) is formed on the planarization layer. An organic light-emitting layer(400) is formed on the first electrode. A second electrode(500) is formed on the organic light-emitting layer.
