Abstract: A polarized light illumination device that is able to utilize both polarized light components by using a plurality of light sources without increasing the illumination angle, and a projection display device that is able to project a considerably bright projection image are provided. In a polarized light illumination device, randomly polarized light emitted from first and second light sources is directionally separated into two types of polarized light by a polarized light separating and synthesizing optical element, secondary light-source images, which are offset in the x direction, are formed, and then, the direction of polarization is aligned.