A thin film transistor array substrate and a repairing method thereof are provided. The thin film transistor array substrate comprises a substrate, plural scan lines, plural data lines, plural common lines, and plural pixels. The scan lines and the data lines are disposed over the substrate and define plural pixel areas. Each pixel is disposed in one of the pixel areas corresponding thereto. Each pixel comprises a thin film transistor, a pixel electrode, a top electrode, and a conductive line. In each pixel, the thin film transistor is coupled to the corresponding scan line and the corresponding data line, and the pixel electrode is disposed over the corresponding common line. Furthermore, the top electrode is disposed between the corresponding pixel electrode and common line, and the conductive line is disposed out of the corresponding common line and coupled between the corresponding top electrode and pixel electrode.