The present application relates to a substrate for an organic material electronic device and a use thereof. The present application can provide a substrate, which is applied to the construction of a flexible device comprising a structure in which an organic material layer and an inorganic material layer coexist, so as to have excellent interfacial adhesion thereby preventing stripping of the organic material layer and the inorganic material layer. Also, the present application can provide an organic material electronic device having excellent durability as well as excellent required physical properties, such as light extraction efficiency, by using the substrate for the organic material electronic device.