The present invention provides a projection display system comprising: illumination lights of plural colors emitted from plural laser light sources; an illumination optical system for illuminating the illumination light of at least one of the colors in an beam axis or in an illumination range, either of which is different from the other colors; a deflection mirror device for modulating the illumination lights of respective colors in the same deflection angle, with the modulation of each color being performed in sequence within one frame; a projection optical system for projecting the reflection light of the illumination light from the deflection mirror device; and a laser light source control circuit for controlling the intensity of the illumination light of each color, wherein the laser light source control circuit performs adjustment so that the ratio of intensity of each of the colors is a prescribed ratio.