disclosed is a method for realizing gray levels of a liquid crystal display device , which realize various gray levels by interworking a gamma voltage and a sub - frame . the method includes the steps of dividing a liquid crystal response time interval for a pixel during one frame into n sequential sub - frames , enabling the pixel and applying a gamma voltage having a fixed level to the pixel , filling electric charges in the pixel by using the gamma voltage during each of the n specific sub - frames , and disabling the pixel at an end time point of a predetermined i th sub - frame , the i being an integer , wherein an amount of light projected on the pixel is adjusted by regulating a time point at which the pixel is disabled during each of the n specific sub - frames .