The present disclosure relates to an array substrate and a method for manufacturing the same. The array substrate includes a thin film transistor and comprises at least a first region and a second region. A thickness of an active layer of the thin film transistor in the first region is different from that of an active layer of the thin film transistor in the second region. A ratio of the overlapped area between the source electrode or the drain electrode and the active layer of the thin film transistor to the thickness of the active layer is kept uniform over the first region and the second region.