An array substrate and a display device are disclosed. The array substrate includes: a base substrate; gate lines and data lines disposed on the base substrate; and display units defined by intercrossing of the data lines and the gate lines, in which each display unit is provided with a thin-film transistor, a sub-pixel electrode and a common electrode line; and the common electrode line comprises a main electrode line, an extension direction of which is the same as an extension direction of the gate lines, and branch electrode lines connected with the main electrode line. The present disclosure reduces the overall resistance of common electrode lines by branch electrode lines connected with main electrode lines, effectively reduces the phenomenon of common electrode signal delay and improves the display quality of a display panel.