The disclosure relates to an array substrate, a manufacturing method thereof, a display panel and a display device. The array substrate comprises a gate insulation layer, a plurality of pixel electrodes, data lines and protective patterns, wherein the pixel electrodes are arranged on the gate insulation layer; the data lines are arranged between every two adjacent pixel electrodes; the protective patterns are arranged at one side, far away from the gate insulation layer, of each data line; orthographic projections of the data lines on the gate insulation layer are smaller than that of the protective patterns on the gate insulation layer, and the orthographic projections of the protective patterns on the gate insulation layer and orthographic projections of the pixel electrodes on the gate insulation layer are free of an overlapping area. According to the array substrate, the manufacturing method thereof, the display panel and the display device, parasitic capacitance between the data lines and adjacent pixel electrodes can be effectively reduced.