The present invention relates to a TFT-LCD array substrate and a driving method thereof. The TFT-LCD array substrate comprises a substrate, on which pixel regions arranged in matrix are formed, a first pixel electrode and a first thin film transistor located in an odd column and a second pixel electrode and a second thin film transistor located in an even column are formed in each pixel region; a first gate line and a second gate line are formed in each pixel region, the first gate line is connected to gate of the first thin film transistor, and the second gate line is connected to gate of the second thin film transistor; one data line is formed in each pixel region, and the data line is connected to source of the first thin film transistor and source of the second thin film transistor, respectively. The present invention reduces the number of data lines and the number of data driving chips or the pins thereof, or, reduces the number of the gate lines and the number of scan driving chips or the pins thereof, and reduces the production cost of the TFT-LCD.