A semiconductor light emitting device includes: a stacked body including a first and a second semiconductor layers of a first and second conductivity types respectively, and a light emitting layer provided between thereof; a first and a second electrodes in contact with the first and second semiconductor layers respectively. Light emitted is resonated between first and second end surfaces of the stacked body opposed in a first direction. The second semiconductor layer includes a ridge portion and a wide portion. A width of the ridge portion along a second direction perpendicular to the first and the stacking directions is narrower on the second electrode side than on the light emitting layer side. A width of the wide portion along the second direction is wider than the ridge portion. A width of the narrow part of the second electrode along the second direction is narrower than that on the ridge portion