The present invention provides an organic light emitting device comprising: a substrate; a first conductive layer and a second conductive layer, which are sequentially positioned on the substrate; and at least one organic material layer, including a light emitting layer, which is interposed between the first conductive layer and the second conductive layer; wherein the organic light emitting device comprises a pattern layer formed corresponding to the light emitting region between at least one organic material layer and at least one conductive layer of the first conductive layer and the second conductive layer; charges are injected or transported between the conductive layer and the organic material layer through the pattern layer; and charges are not directly injected or transported in the region in which two layers each in contact with the upper surface and the lower surface of the pattern layer are directly in contact, and a method for preparation thereof.