To provide a lighting device irradiating light downwards from an opening formed on a ceiling plate, wherein a box body housing lighting fixtures is mounted on the backside of a ceiling; an eave covers the inside face of the ceiling plate; the opening is gently observed from the lower face of the ceiling plate when looking up the opening of the ceiling plate from downside by the arrangement of a slanted part; thus, appearance is not damaged; the light is prevented from reflecting downward by a dazzle prevention means of the slanted part; the illumination light is not reflected at the inner face of the opening of the ceiling plate; and uncomfortable feeling is prevented.

On a lighting device, irradiating light downwards from an opening formed on a ceiling plate, of which, a box body housing lighting fixtures is mounted on the backside of a ceiling, and an eave covering the inner face of the opening is formed on the inner face of the opening of the ceiling plate, the eave has a slanted part slanting from the lower side face of the ceiling plate toward the upper side face thereof, and the slanted part has the dazzle prevention means.