A surface-mount type semiconductor light emitting device comprising: a package having a recess formed in an upper face thereof; a pair of lead frames buried in the package so that respective one ends of the pair of lead frames are exposed at a bottom of the recess and respective another ends of the pair of lead frames protrude to an exterior from a side face of the package; a light emitting element arranged on the upper face of at least either one of the pair of lead frames exposed at the bottom of the recess; and an encapsulant filled in the recess, wherein the package includes, at the side face where the pair of lead frames protrudes: a first side face formed inwardly relative to a frame side face of the pair of lead frames; wherein a second side face formed at a lower portion of the first side face and protruded so as to cover a top face of the pair of lead frames and so as to cover an upper part of a bent portion of the pair of lead frames in a view from a direction perpendicular to a plane on which the semiconductor light emitting device is to be mounted, wherein the semiconductor light emitting device has a structure adapted to be mounted to a plane parallel to the bottom of the recess, wherein the pair of lead frames protruding to the exterior from the side face of the package are bent along the side face of the package and a bottom face thereof, the first side face is formed inwardly relative to the frame side face of the pair of bent lead frames, and a height of the first side face in the thickness direction of the package is larger than a height of the second side face in the thickness direction of the package. a package having a recess formed in an upper face thereof; a pair of lead frames buried in the package so that respective one ends of the pair of lead frames are exposed at a bottom of the recess and respective another ends of the pair of lead frames protrude to an exterior from a side face of the package; a light emitting element arranged on the upper face of at least either one of the pair of lead frames exposed at the bottom of the recess; and an encapsulant filled in the recess, wherein the package includes, at the side face where the pair of lead frames protrudes: a first side face formed inwardly relative to a frame side face of the pair of lead frames; wherein a second side face formed at a lower portion of the first side face and protruded so as to cover a top face of the pair of lead frames and so as to cover an upper part of a bent portion of the pair of lead frames in a view from a direction perpendicular to a plane on which the semiconductor light emitting device is to be mounted, wherein the semiconductor light emitting device has a structure adapted to be mounted to a plane parallel to the bottom of the recess, wherein the pair of lead frames protruding to the exterior from the side face of the package are bent along the side face of the package and a bottom face thereof, the first side face is formed inwardly relative to the frame side face of the pair of bent lead frames, and a height of the first side face in the thickness direction of the package is larger than a height of the second side face in the thickness direction of the package. a first side face formed inwardly relative to a frame side face of the pair of lead frames; wherein a second side face formed at a lower portion of the first side face and protruded so as to cover a top face of the pair of lead frames and so as to cover an upper part of a bent portion of the pair of lead frames in a view from a direction perpendicular to a plane on which the semiconductor light emitting device is to be mounted, wherein the semiconductor light emitting device has a structure adapted to be mounted to a plane parallel to the bottom of the recess, wherein the pair of lead frames protruding to the exterior from the side face of the package are bent along the side face of the package and a bottom face thereof, the first side face is formed inwardly relative to the frame side face of the pair of bent lead frames, and a height of the first side face in the thickness direction of the package is larger than a height of the second side face in the thickness direction of the package.