A light emitting device comprising: a resin package provided with a recess portion defined by a side surface and a bottom surface; a light emitting element housed in the recess portion of the resin package; and a light transmissive sealing member filled in the recess portion of the resin package to cover the light emitting element; wherein the resin package has a first lead and a second lead which are disposed so as not to be exposed from two opposing outer side surfaces of the resin package but are exposed from the other two opposing outer side surfaces of the resin package which are perpendicular to the two opposing outer side surfaces, wherein the resin package has a resin portion integrally formed with the first and second leads (22a, 22b), wherein the first and the second leads (22a, 22b) are disposed so that their top surfaces are exposed from the resin portion on the bottom surface of the recess portion, wherein the region of the top surfaces of the first lead and the second lead corresponding to the bottom surface of the recess portion of the resin package is lower than its surrounding region of the top surface of the first and the second lead (22a, 22b), characterized in that the region of the top surfaces of the first lead and the second lead exposed from the other two opposing outer side surfaces of the resin package is lower than the region of the top surfaces of the first lead and the second lead in contact with the resin portion, and in that the region of the top surfaces of the first and the second lead corresponding to the bottom surface of the recess portion of the resin package is lower than the region of the top surfaces of the first lead and the second lead exposed from the other two opposing outer side surfaces. a resin package provided with a recess portion defined by a side surface and a bottom surface; a light emitting element housed in the recess portion of the resin package; and a light transmissive sealing member filled in the recess portion of the resin package to cover the light emitting element; wherein the resin package has a first lead and a second lead which are disposed so as not to be exposed from two opposing outer side surfaces of the resin package but are exposed from the other two opposing outer side surfaces of the resin package which are perpendicular to the two opposing outer side surfaces, wherein the resin package has a resin portion integrally formed with the first and second leads (22a, 22b), wherein the first and the second leads (22a, 22b) are disposed so that their top surfaces are exposed from the resin portion on the bottom surface of the recess portion, wherein the region of the top surfaces of the first lead and the second lead corresponding to the bottom surface of the recess portion of the resin package is lower than its surrounding region of the top surface of the first and the second lead (22a, 22b), characterized in that the region of the top surfaces of the first lead and the second lead exposed from the other two opposing outer side surfaces of the resin package is lower than the region of the top surfaces of the first lead and the second lead in contact with the resin portion, and in that the region of the top surfaces of the first and the second lead corresponding to the bottom surface of the recess portion of the resin package is lower than the region of the top surfaces of the first lead and the second lead exposed from the other two opposing outer side surfaces.