Organic light emitting display and preparation method thereof

The invention provides an organic light emitting display. An organic light emitting diode (OLED) is directly arranged on a substrate, the amount of film layers penetrated by emergent light of the OLED is reduced, the color coordinate offset of the OLED is reduced, and the display quality is improved. A source electrode and a drain electrode in an insulation layer of a thin film transistor can form a capacitor, the area of a non-light-emitting area is greatly reduced, and the aperture ratio of the display is improved. The invention provides a preparation method of the organic light emitting display. According to the preparation method, the steps of preparing a planarization layer and an interlayer insulation layer between the isolated source/drain electrode layer and the insulation layer are omitted, the source electrode and the drain electrode in the insulation layer of the thin film transistor can form the capacitor to greatly reduce the production steps, the technology is simple, and the preparation cost is effectively reduced.