It is possible to manufacture a large-size, high-accuracy organic EL display using a plastic substrate and an organic EL display using a roll-shaped long plastic substrate.The organic EL display includes an organic EL device A having at least a lower electrode 300, an organic layer including at least a light emitting layer, and an upper electrode 305 and a thin film transistor B on a transparent plastic substrate 100, a source electrode or drain electrode of the thin film transistor B is connected to the lower electrode 300, the plastic substrate 100 has a gas barrier layer 101a, the thin film transistor B is formed on the gas barrier layer 101a, the thin film transistor B includes an active layer 203 containing a non-metallic element which a mixture of oxygen (O) and nitrogen (N) and has a ratio of N to O (N number density/O number density) from 0 to 2, and the organic EL device A is formed at least on the gas barrier layer 101a or one the thin film transistor B.