The present disclosure provides a method of manufacturing array substrate, including: providing a substrate; and forming a metal layer, a gate layer, an insulation layer, and a protective layer on the substrate sequentially. Wherein, the metal layer is formed on a drive line on the substrate, and the metal layer is arranged in at least one of a position between the substrate and the insulation layer and a position between the insulation layer and the protective layer. In the present disclosure, an electrostatic discharge path is increased through the floating metal layer. Even though the floating metal layer is burned down, a display quality would not be affected, the product yield is improved. Besides, it only needs to adjust a photomask pattern. Therefore, a production procedure needs not to be adjusted.