A light guide device and a liquid crystal display module and a liquid crystal display device having the light-guide device that can minimize the flowing of a light guide plate received in a mold frame by improving the structure of the light guide plate of the liquid crystal display device. A light guide device for receiving a light from a lamp unit and guiding the light to a display unit for displaying an image has a catching jaw is formed by cutting off both corner portion of a first end portion to which the light from the lamp unit is inputted. The width of the first end portion including the catching jaw is wider than the width of a second end portion opposite to the first end portion. Therefore, the catching amount of a catching boss integrally formed with the mold frame and the catching jaw of the light guide plate is remarkably increased and the light guide plate is prevented from being flowed towards the lamp even when exterior impacts are applied to the liquid crystal display device.