An array substrate, a manufacturing method thereof and an application of the array substrate are provided. The array substrate comprises a substrate and a data line above the substrate, the data line comprising a first surface closest to the substrate and parallel to a bottom surface of the substrate. The array substrate further comprises a light shielding layer above the substrate, and the light shielding layer is configured to cover the data line, such that at least a portion of the data line in the display area of the array substrate is not exposed. When the array substrate is applied to a display device, the amount of light leakage at the data line can be reduced.