A semiconductor light emitting device includes a semiconductor light emitting element, a lead electrically connected to the semiconductor light emitting element, and a resin package covering the semiconductor light emitting element and part of the lead. The resin package includes a lens facing the semiconductor light emitting element. The lead includes an exposed portion that is not covered by the resin package. The exposed portion includes a first portion and a second portion, where the first portion has a first mount surface oriented backward along the optical axis of the lens, and the second portion has a second mount surface oriented perpendicularly to the optical axis of the lens.