A thin film transistor array comprising a substrate, thin film transistors, pixel electrodes, common lines, and auxiliary electrodes disposed on the substrate is provided. The substrate has a plurality of pixel regions, and each of the thin film transistors, pixel electrodes, and auxiliary electrodes are disposed in each pixel region. In each pixel region, the pixel electrode is covered over the common line and is electrically connected to the thin film transistor. The auxiliary electrode is located between the pixel electrode and the common line, and the area of the overlapping region between the auxiliary electrode and the common line is L×H, while the sum of the side lengths of the overlapping region is more than 2L×2H, wherein L and H are both positive real numbers. The individual feed-through voltages in each pixel regions in the thin film transistor array are the same.