Illumination systems are disclosed that illuminate a surface (M) for irradiation with illumination light emitted from a light source (5). An exemplary illumination system includes an incidence-side reflection-type fly-eye optical system (12) having multiple reflection-type partial optical systems arranged in rows, an emission-side reflection-type fly-eye optical system (14) having multiple reflection-type partial optical systems arranged in rows and corresponding to respective reflection-type partial optical systems of the incidence-side reflection-type fly-eye optical system (12), and a condensing optical system including two reflecting mirrors (18, 20) that guide illumination light, reflected by the emission-side reflection-type fly-eye optical system (14), to the surface (M). The center of curvature of at least one of the reflecting mirrors is optically eccentric with respect to a normal to the surface for irradiation at the center of the illuminated region.