A scan driver includes a control unit, a first output unit, a second output unit, and a masking control unit. The control unit outputs a first control signal to a first control node and outputs a second control signal to a second control node. The first output unit is connected to the first control node, a first output terminal, and a first voltage terminal, and operates in response to the first control signal. The second output unit is connected to the second control node, the first output terminal, and a second voltage terminal, and operates in response to the second control signal. The masking control unit is connected between an input terminal, to which a clock signal is input, and the first control node and controls a voltage level of the first control signal in response to a masking enable signal.