Disclosed are a method, a device and a source driver for charging pixel points on a TFT-LCD substrate, which are capable of charging electrodes on an upper substrate and pixel points on a lower substrate. The charging method includes: switching on a first, second, third and fourth switches, switching off a fifth, sixth and seventh switches, and charging a first, second, third and fourth capacitors; switching off the first, second, third, fourth, sixth and seventh switches, and charging a fifth capacitor; switching off the fifth switch, switching on the first, second, third, fourth, sixth and seventh switches, so that the first capacitor stores positive six-bit pixel voltage and the fourth capacitor stores negative six-bit pixel voltage; and charging the pixel points on the lower substrate by the first and fourth capacitors, and charging the electrodes on the upper substrate by the fifth capacitor.