A steering wheel including a pad portion mounted on a boss portion, a ring portion supported on the boss portion via spokes, a horn button mounted on an upper surface of the pad portion, and a display portion of a luminous display device. The display portion is mounted on a part of the pad portion close to the driver's side, and the horn button is mounted on the part of the pad portion close to a front window of a vehicle. Only the part of the pad portion on which the display portion is mounted is inclined toward the driver's side so that the front window does not fall within a light projecting region of said display portion. The luminous display device includes a translucent light-dissipation plate mounted in an opening of a reflection chamber. The thickness of the dissipation plate becomes progressively smaller away from a main light-emitting element provided within the reflection chamber. A sub light-emitting element is mounted below a character plate and disposed close to the reflection chamber. A light-reducing wall is provided between the dissipation plate and the main light-emitting element so as to prevent the lights, emitted respectively from the main and sub light-emitting elements, from being mixed together.