The present disclosure relates to the field of display technologies, and in particular to a thin film transistor and a method for manufacturing the same, an array substrate and a display device. An active layer of the thin film transistor includes at least two metal oxide semi-conductor layers, the at least two metal oxide semi-conductor layers include a channel layer and a first protection layer, and metals in the channel layer include tin, and at least one of indium, gallium and zinc. The first protection layer includes praseodymium used to absorb photo-generated electrons from at least one of the channel layer and the first protection layer which is under light irradiation and reduce a photo-generated current caused by the light irradiation.