Each of thin film deposition assemblies of a thin film deposition apparatus includes: a deposition source that includes a deposition material; a deposition source nozzle unit arranged at a side of the deposition source and including a plurality of deposition source nozzles arranged in a first direction; a patterning slit sheet arranged opposite to the deposition source nozzle unit and having a plurality of patterning slits arranged in the first direction; and a barrier plate assembly including a plurality of barrier plates arranged in the first direction, the barrier plate assembly being arranged between the deposition source nozzle unit and the patterning slit sheet. The thin film deposition apparatus and the substrate are separated from each other and are movable relative to each other. The deposition material includes a material to produce the thin film of a red (R), green (G) or blue (B) emission layer, or an auxiliary layer.