A headphone device includes a head pad, a band, and a sleeve. The head pad has a curved shape with a first radius of curvature. The band extends from an edge of the head pad into a curved shape with a second radius of curvature different from the first radius of curvature, and supports a housing, via a hanger, housing a speaker unit. The sleeve has a curved shape with the first radius of curvature and is slidable along the head pad to cover the band so as to change the radius of curvature at a part of the band covered with the sleeve to approximate to the first radius of curvature.