To obtain an illuminator and a projector using the illuminator by which a liquid crystal display element is effectively illuminated while effectively using a luminous flux from a light source.

This illuminator is provided with the light source 1, an elliptic reflector 2 leading the luminous flux from the light source 1 in the direction of an irradiated surface and also forming the image of the light source 1, a rod integrator 5 totally reflecting the luminous flux from a light source image by a prismatic surface, a relay lens group 6 forming a secondary light source image from the light source image and an optical element leading the luminous flux from the secondary light source image to the irradiated surface. In this case, a lens G1 whose surface on the side of the light source 1 arranged on the closest side of the light source 1 out of the relay lens group 6 is made as a plane and whose size is larger than that of a light-emitting surface is brought into contact with the light-emitting surface of the rod integrator 5.