An organic light emitting display (OLED) device includes: an insulating substrate; a first electrode on the insulating substrate; a second electrode on the first electrode; a light-emitting layer between the first electrode and the second electrode; a hole common layer between the first electrode and the light-emitting layer; an electron common layer between the second electrode and the light-emitting layer; and a scattering layer on the insulating substrate and having a non-planar surface, wherein the scattering layer includes at least one of benzene, naphthalene, anthracene, tetracene, pentacene, amine, benzidine, biphenyl, carbazole, pyridine, bipyridine, imidazole, phenanthroline, phenylborane, pyrimidine, or triazine, and the base material of the scattering layer includes a substituent including at least one of a benzoyl group, a carboxyl group, an aminophenoxyl group, a tricabonate group, or a styryl group.