A semiconductor light emitting device, comprising: a semiconductor layer having a first face, a second face on a side opposite to the first face, and a light emitting layer; a p-side electrode provided on a first region on the second face side, the first region including the light emitting layer; an n-side electrode provided on a second region layer on the second face side, the second region not including the light emitting layer; a first insulating film provided on the second face side and having a first opening communicating with the p-side electrode and a second opening communicating with the n-side electrode; a p-side interconnection (19, 21, 23) provided on the first insulating film and electrically connected to the p-side electrode through the first opening; and an n-side interconnection (19, 22, 24) provided on the first insulating film, the n-side interconnection (19, 22, 24) being separated from the p-side interconnection (19, 21, 23) and electrically connected to the n-side electrode through the second opening, the p-side interconnection (19, 21, 23) having a plurality of protrusive parts protruding toward the n-side interconnection (19, 22, 24), and the n-side interconnection (19, 22, 24) having a plurality of portions extending between the protrusive parts of the p-side interconnection (19, 21, 23) and the p-side interconnection (19, 21, 23) includes a p-side interconnection layer having the plurality of protrusive parts, and provided both inside the first opening and on the first insulating film, and a p-side metal pillar provided on the p-side interconnection layer, the p-side metal pillar being thicker than the p-side interconnection layer; and the n-side interconnection (19, 22, 24) includes an n-side interconnection layer having the plurality of portions extending between the protrusive parts, and provided both inside the second opening and on the first insulating film, and an n-side metal pillar provided on the n-side interconnection layer, the n-side metal pillar being thicker than the n-side interconnection layer, characterised in that: the plurality of protrusive parts and the plurality of portions are positioned between the p-side metal pillar and the n-side metal pillar. a semiconductor layer having a first face, a second face on a side opposite to the first face, and a light emitting layer; a p-side electrode provided on a first region on the second face side, the first region including the light emitting layer; an n-side electrode provided on a second region layer on the second face side, the second region not including the light emitting layer; a first insulating film provided on the second face side and having a first opening communicating with the p-side electrode and a second opening communicating with the n-side electrode; a p-side interconnection (19, 21, 23) provided on the first insulating film and electrically connected to the p-side electrode through the first opening; and an n-side interconnection (19, 22, 24) provided on the first insulating film, the n-side interconnection (19, 22, 24) being separated from the p-side interconnection (19, 21, 23) and electrically connected to the n-side electrode through the second opening, the p-side interconnection (19, 21, 23) having a plurality of protrusive parts protruding toward the n-side interconnection (19, 22, 24), and the n-side interconnection (19, 22, 24) having a plurality of portions extending between the protrusive parts of the p-side interconnection (19, 21, 23) and the p-side interconnection (19, 21, 23) includes a p-side interconnection layer having the plurality of protrusive parts, and provided both inside the first opening and on the first insulating film, and a p-side metal pillar provided on the p-side interconnection layer, the p-side metal pillar being thicker than the p-side interconnection layer; and the n-side interconnection (19, 22, 24) includes an n-side interconnection layer having the plurality of portions extending between the protrusive parts, and provided both inside the second opening and on the first insulating film, and an n-side metal pillar provided on the n-side interconnection layer, the n-side metal pillar being thicker than the n-side interconnection layer, characterised in that: the plurality of protrusive parts and the plurality of portions are positioned between the p-side metal pillar and the n-side metal pillar.