The present application provides an array substrate and a manufacturing method thereof, and a display device, to solve the problem in the prior art that the resistance of the common electrode is large due to an improper layout of the common electrode so that the common electrode is easily affected by other signals to cause voltage fluctuation and thus the quality of the display is influenced. In the array substrate and the manufacturing method thereof, and the display device provided in the present application, since the first common electrode is provided in the source/drain metal layer and the second and third common electrodes are further formed, connection of the first, second and third common electrodes effectively enables a low-resistance common electrode, which is not easily influenced by other signals to cause voltage fluctuation, therefore, the quality of the display can be improved.