A gate driver, a display apparatus having the same, and a gate driving method are provided. The display apparatus includes a plurality of pixels, a data driver circuit, and a gate driver circuit. The gate driver circuit includes M groups of gate channels. Each of the M groups of gate channels includes a control circuit and an output buffer. The control circuit receives a power supply voltage from a power supply circuit and generates a modulated supply voltage. The output buffer is connected to the control circuit, the output buffer is powered by the modulated supply voltage to output a gate signal to a gate line of the display panel, wherein a driving pulse of the gate signal is shaped during a charge period according to the modulated supply voltage, and the shape of the driving pulse of the gate signal is maintained during a pre-charge period.