Embodiments of the present invention disclose a display back plate. The display back plate comprises: an array substrate; and a pixel define layer formed on the array substrate and for defining an organic light emitting unit. An accommodation space is provided in the pixel define layer and a water absorbent material is provided within the accommodation space; the accommodation space has an opening formed in an upper surface and/or a lower surface of the pixel define layer; and the accommodation space is separated from the organic light emitting unit such that the water absorbent material within the accommodation space is spaced away from the organic light emitting unit. Embodiments of the present invention enable absorption of water vapor inside the organic light emitting display device, to prevent the adverse affection of water vapor on performance of the organic light emitting display device, so as to prolong service life of the organic light emitting display device.