An image display apparatus and an image optimization method are provided. The image display apparatus includes an image content analyzer, a luminance compensator, and an image optimization processor The image content analyzer receives image data and ambient luminance and generates a backlight luminance adjustment value according to the image data and the ambient luminance. The luminance compensator generates an image data luminance adjustment value according to the backlight luminance adjustment value and generates first image data by adjusting the luminance of the image data according to the image data luminance adjustment value. The image optimization processor generates a saturation adjustment weight according to the image data luminance adjustment value. According to the saturation adjustment weight, the image optimization processor generates output image data by adjusting the luminance of the first image data.