According to one embodiment, a semiconductor light emitting device includes a semiconductor layer, a p-side electrode, an n-side electrode, a p-side metal pillar, an n-side metal pillar, and an insulator. The semiconductor layer includes a first surface, a second surface opposite to the first surface, and a light emitting layer. The p-side metal pillar includes a p-side external terminal. The n-side metal pillar includes an n-side external terminal. At least one selected from an area and a planar configuration of the p-side external terminal is different from at least one selected from an area and a planar configuration of the n-side external terminal.