To make keys to be touched visible even if the front sides of keys are concealed by the palms of the hands, etc.

The keyboard device is constituted by providing a keyboard chassis 2 arranged with the keys (hereafter only the white keys 3 are explained) having light transparency turnably in a vertical direction with luminous bodies 14 for the white keys in correspondence to the front lower sides of the white keys 3 and causes the luminous bodies 14 to emit light in this state to glitter the front sides of the white keys 3 by illumination from below this side. The white keys 3 are provided with light transmission members 20 for the white keys 3 to introduce part of the light emitted by the luminous bodies 14 to the rear sides of the white keys 3. Then, the light from the luminous bodies 14 illuminates the front sides of the white keys 3 and part of the light is introduced by the light transmission members 20 and is emitted from the rear sides of the white keys 3 and therefore the front sides and rear sides of the white keys 3 may be simultaneously glittered, by which the rear sides of the white keys 3 are glittered even if the front sides of the white keys 3 are concealed by the player' hands when the plural white keys 3 are simultaneously touched in order to play chords or the like and therefore the player is able to surely visually recognize the white keys 3 to be touched without missing.