An excimer lamp which can emit UV radiation with a high degree of efficiency and high degree of uniformity, has a UV-reflecting film that does not peel. The excimer lamp is fitted with a silica glass discharge vessel that encloses a discharge gas which forms excimer molecules by dielectric barrier discharge in an internal space enclosed by a top wall panel, a bottom wall panel, side wall panels and end panels and with an electrode on both the outer surface of the top wall panel and another electrode on the outer surface of the bottom wall panel. On the inner surface of the discharge vessel, a UV-reflecting film comprised of silica and alumina particles is formed, at least, on the inner surface area of the side wall panels with the silica particles composing at least 30 weight % of the UV-reflecting film.