A new 2D/3D switchable display apparatus matches a polarization direction of light output from a 2D image display panel with a rubbing direction of a lower alignment layer of a liquid crystal lens, and tilts a rubbing direction of an upper alignment layer of the liquid crystal lens and a direction of a polarization axis of a polarizer at a predetermined angle, thereby reducing a loss of light passing through the liquid crystal lens, making it possible to improve luminance of images, improve the quality of 3D images in the horizontal direction, prevent or reduce color separation and moire phenomena, and reduce the manufacturing cost.