The present disclosure relates to a display device, an array substrate and a manufacturing method thereof, and relates to the technical field of display. The method includes steps of: providing a base substrate, and forming a semiconductor pattern, a gate insulation layer, a gate electrode, an insulation layer and a source/drain electrode on the base substrate, and further includes forming the composite material layer on the base substrate including the semiconductor pattern, and hydrotreating the composite material layer, in which the composite material layer may contain titanium complex-graphene oxide. The present disclosure is capable of omitting the interlayer insulation layer, thereby avoiding the situation that a flexible layer cannot be displayed due to the breakage of insulation layer between inorganic layers, thereby improving bending performance of the flexible screen.