An array substrate, a manufacturing method thereof, and a display device are provided. The array substrate includes a peripheral common electrode line for supplying a common voltage and a plurality of sub-pixels. The array substrate further includes first connection portions and second connection portions; the first connection portions extend along a first direction and are provided between the peripheral common electrode line and common electrodes of the sub-pixels adjacent to a side of the peripheral common electrode line along a second direction, for electrically connecting the peripheral common electrode line with the common electrodes of the sub-pixels adjacent to the side of the peripheral common electrode line along the second direction; and the second connection portions extend long the first direction and are provided between the common electrodes of adjacent sub-pixels along the first direction, for electrically connecting the common electrodes of the adjacent sub-pixels along the first direction.