A wordline driver includes a pre-driver, a sub-wordline driver and a transmission circuit. The pre-driver generates a wordline enable signal and a wordline disable signal based on one or more selection signals, a decoded address signal, and one or more timing control signals. The transmission circuit transmits the wordline enable signal and the wordline disable signal. The sub-wordline driver controls a voltage level of the sub-wordline based on the wordline enable signal and the wordline disable signal that are transmitted by the transmission circuit. Therefore, driving capacity may be improved.