An embodiment of the invention provides an array substrate, a manufacturing method of the array substrate, and a display device, and relates to the technical field of display. The manufacturing method includes steps of 1, forming a pattern layer with a grid electrode on a substrate; 2, forming a pattern layer with a grid insulation layer on the substrate subjected to the last step; 3, forming a pattern layer with an active layer on the substrate subjected to the second step; 4, sequentially forming a transparent conductive thin film and a metal thin film on the substrate subjected to the third step, and forming a pattern layer with a first electrode, a data line, a source electrode, a drain electrode and a thin film transistor (TFT) channel through pattern composition process; 5, forming a pattern layer with a passivated layer on the substrate subjected to the fourth step; and 6, forming a pattern layer with a second electrode on the substrate subjected to the fifth step. The manufacturing method is used for manufacturing the array substrate and the display device and the like. The array substrate, the manufacturing method of the array substrate and the display device have the advantages that pattern composition process times can be decreased, and accordingly, productivity of mass production products is improved, and cost is reduced.