The invention relates to a shift register and a liquid crystal display grate drive device. The shift register comprises two thin film transistors, a compensation starting voltage unit, and low level preservation units. A grate drive circuit consists of a plurality of shift registers, wherein the compensation starting voltage unit is formed by the thin film transistors and a capacitor. The shift register and the grate drive device using the shift register compensate the starting voltage of certain important thin film transistors by the compensation starting voltage unit, thereby the thin film transistors can still work after being compensated under the starting voltage applied thereon after working a period of time, though the starting voltage of the thin film transistors gradually increases along with positive bias voltage, and the thin film transistors have prolonged service life. In addition, the shift register also can quick transform an output level of an output signal from high level to low level. Besides, when the output signal needs output a low level, the low level state of the output signal can be well maintained.