To prevent dust from adhering to an image forming element and an optical element in its periphery while securing favorable cooling efficiency and maintainability.

This image projector includes: a lighting optical system ; a color separating and synthesizing optical system, which performs color separation for light from the lighting optical system and guides the color separation light to a plurality of image forming elements 58R, 58G, 58B, and synthesizes the light from the plurality of image forming elements; a projecting optical system 5; optical storing members 6, 7 for storing the lighting optical system and the color separating and synthesizing optical system in the interior thereof; and a cooling air duct 11 for introducing the air passing through a dust-proof member 31a into a first storing space S1 where the color separating and synthesizing optical system is stored in the interior of the optical storing member. Among the plurality of lighting optical elements constituting the lighting optical system, the final lighting optical element 47a disposed closest to the color separating and synthesizing optical system closes the first storing space to a second storing space S2 where the lighting optical elements except the final lighting optical element are stored in the interior of the optical storing member.