Provided is an organic light emitting display comprising: a substrate including a light emitting zone and a non-light emitting zone, which is positioned around the outside of the light emitting zone; at least one organic light emitting diode formed on the light emitting zone; an encapsulation layer for sealing the organic light emitting diode; and a dam formed on the non-light emitting zone, wherein the encapsulation layer includes a structure in which at least one inorganic layer and at least one organic layer are alternatingly stacked, wherein the organic layer is made from a display sealing material composition, and wherein the display sealing material composition comprises a photo-curable monomer and a photopolymerization initiator. The photo-curable monomer comprises: a monomer not having an aromatic hydrocarbon group; and a monomer, represented by chemical formula 1, having at least two substituted or non-substituted phenyl groups, wherein the photo-curable monomer comprises approximately 5 wt. % to 45 wt. % of the monomer having the at least two substituted or non-substituted phenyl groups, and approximately 55 wt. % to 95 wt. % of a monomer not having the aromatic hydrocarbon group.