An LCD device includes a driver and a timing controller. The driver includes at least one or more gate driving IC for outputting a scan signal to a plurality of gate lines of a panel, and at least one or more data driving IC for respectively outputting a plurality of image data signals to a plurality of data lines of the panel. The timing controller determines whether a current mode is an abnormal mode in which the panel outputs an abnormal image by using at least one or more lock signals, outputs a driver control signal generated for controlling the driver when the current mode is determined as a normal mode, and outputs a masking control signal, which makes the panel not to output the abnormal image, to the driver when the current mode is determined as the abnormal mode.