In the optical composite sheet according to an embodiment, optical functional elements such as a prism sheet and a light diffusion layer are combined, and a light absorbing layer that selectively absorbs light of a specific wavelength band is inserted, so that the optical performance and color gamut can be enhanced as compared with the prior art. In particular, it is possible to minimize the decrease in luminance due to the absorption of light by the light absorbing layer while enhancing the color gamut by adjusting the lamination configuration of the optical composite sheet.