To provide a gate driver and an operation method of the driver.

The gate driver for use in a liquid crystal display device has a plurality of shift registers connected in series. Each of the shift registers is used to provide a gate-line drive signal to a row of pixels in the liquid crystal display. The gate-line drive signal has a front pulse and a rear pulse, and the shift register has a front-pulse generating part and a rear-pulse generating part for generating to corresponding pulse. Each of the pulse generating parts has a first pull-up circuit to generate a voltage level to keep a switching element in a second pull-up circuit in a conducting state, so as to generate a front pulse or a rear pulse, in response to a corresponding clock signal and to allow two pull-down circuits, in response to the voltage level, to generate the front pulse or the rear pulse only at a pull-down period.