A projection type color display device capable of achieving both the color balance and higher luminous flux amount (high luminance) of enlarged on-screen images is disclosed. The device includes a white light source, light flux separating unit, image display elements, photosynthetic unit, and a projection lens device. The light intensities of light fluxes of three primary colors of red, green and blue as split by the light flux separating unit are modulated by the image display elements which are provided in a way corresponding to respective ones and then synthesized together by the photosynthetic unit for enlarged projection onto a screen by the projection lens device. During red image displaying, a red image signal is input to the red image display element while performing modulation by the blue image display element based on a signal obtained by adding to a blue image signal a signal with its amplitude being 1/n times the amplitude of the red image signal.