A showcase comprising an illumination apparatus which includes a shade member constituted of a light-transmitting front wall positioned on the side of the light emitting surfaces of LED elements, and a back wall positioned on the side of a substrate provided with the LED elements, the front wall comprising a curved portion having an arc-like section and a pair of flat portions extended continuously from both ends of the curved portion to intersect with the back wall at an acute angle, corner portions where the flat portions intersect with the back wall being a pair of engaging portions; and a holder provided with a plurality of engagement portions and the like with which the engaging portions are disengageably engaged.