A method and apparatus for simulating video data of a liquid crystal display (LCD) device is disclosed. The simulation method includes providing voltage-versus-transmittance data and viewing angle-versus-transmittance data, which vary with a liquid crystal mode, using an optical simulation, converting the result of the optical simulation into a lookup table in connection with a viewing angle and an applied voltage, matching a driving voltage for gamma setting based on the liquid crystal driving mode to gray level data corresponding to the voltage-versus-transmittance data, and correcting minimum/maximum brightness levels, simulating a user-desired test image on a user interface screen; and correcting a color of data of a test image according to properties of an output panel, and finally displaying the color-corrected image.