Provided is a daylighting device (10) including a daylighting member (11) that has a base having light transparency, a plurality of daylighting portions that are provided on one surface of the base and have light transparency, and gap portions provided between the plurality of daylighting portions; and a light diffusion member (12) that is arranged on a light output surface side of the daylighting member (11) and diffuses light output from the daylighting member (11).