A row decoder circuit includes a decoding unit and first and second wordline driving units. The decoding unit generates a first driving signal and a second driving signal based on a selection signal and wordline voltages. A voltage level of the first driving signal and a voltage level of the second driving signal depend on an operation mode. The first wordline driving unit is connected to a first wordline and outputs one of the first driving signal and the second driving signal as a first wordline driving signal based on first driving control signals. The second wordline driving unit is connected to a second wordline and outputs one of the first driving signal and the second driving signal as a second wordline driving signal based on second driving control signals.