A gate driving circuit and a driving method thereof are provided. The gate driving circuit includes a control signal generator and at least one gate channel set, each of the at least one gate channel set includes a plurality of gate channels, and the plurality of gate channels share a level shifter. The driving method includes generating a plurality of first control signals and a plurality of second control signals according to a gate driver start pulse, and determining that one of the gate channels uses the level shifter during a time period according to the plurality of first control signals and the plurality of second control signals. Therefore, the number of the level shifters can be decreased.