A sub-word line driver includes a substrate, a plurality of gate lines and at least one gate tab. The substrate includes a plurality of isolation areas and a plurality of active areas, where the two active areas are separated by each isolation area, and the isolation areas and the active areas are extended in a first direction and are arranged in a second direction perpendicular to the first direction. The plurality of gate lines are formed on the substrate, where the gate lines are extended in a second direction and are arranged in the first direction. The at least one gate tab is formed on the substrate, where the at least one gate tab is extended in the first direction to cover the isolation area. Incorrect operation of the sub-word line driver may be prevented, and a power consumption of the sub-word line driver may be reduced.