A display device displays video for a virtual image. The display device includes a video generation unit generates image light representing the video, a concave mirror has a reflective surface on which the image light is reflected, and a support mechanism adjusts a position of the concave mirror. The concave mirror has, in each position on the reflective surface, a first radius of curvature in the first direction and a second radius of curvature in a second direction. The first radius of curvature and the second radius of curvature individually change and have different rates of change. The reflective surface has a shape following a partial region on an outer surface of an ellipsoid. The ellipsoid has a radius along the first direction that is greater than a radius along the second direction and a radius along a third direction orthogonal to the first direction and the second direction.