Thin film transistor and manufacturing method thereof, array substrate and manufacturing method thereof, and display device

Provided are a thin film transistor and manufacturing method thereof, array substrate and manufacturing method thereof, and display device. The thin film transistor comprises: an active layer (30); an etch-stop layer (40) disposed on the active layer (30); a covering layer (60) disposed on the etch-stop layer (40), wherein the covering layer (60) comprises at least one of an electrically conductive material layer, a non-optically-transmissive insulation layer and a non-optically-transmissive semiconductor layer; and a source (50a) and a drain (50b) disposed on the covering layer (60), wherein the source (50a) and the drain (50b) are electrically connected to the active layer (30). The covering layer (60) of the thin film transistor can reduce damage caused by ESD occurring at positions where the active layer (30) is to be electrically connected to the source/drain (50a, 50b).