A color image display device is provided to reproduce colors determined by an input video signal in a color space of the display device while keeping a wide color reproducing region of the display device with natural hues. On the assumption that a color space is hypothetically considered so that an input signal is originally in hue in a first color range while an increasing saturation is reproduced with hues changed gradually to a widening direction of color reproduction in a second color range or more, the color converting portion 12 converts a video signal, so that an input video signal 10 is reproduced on a color image displaying portion 13 with a tristimulus value represented in this hypothetical color space, and the color image displaying portion 13 displays, and reproduces, a vivid video image without a feeling of wrongness by making use of a wide color reproduction range of the color image display device.