A three-dimensional image display device including a polarized light module, a non-vertical polarized light barrier grating unit and an image display unit is provided. The polarized light module provides a polarized light. The non-vertical polarized light barrier grating unit is disposed in a light path of the polarized light to modulate the polarized light into a modulated polarized light in interlaced lines for output. The image display unit receives the modulated polarized light from the non-vertical polarized light barrier grating unit, and outputs two or more images with parallax.