Light from a semiconductor light-emitting element travels in all directions. Thus, light that travels in the directions other than a lighting direction cannot be used effectively. Means for forming a semiconductor light-emitting element having tilted side surfaces, and forming a reflective layer on the tilted side surfaces has been proposed. However, since the tilted surfaces are formed by an etching method or the like, it takes a long time to form the tilted surfaces, and it is difficult to control the tilted surfaces. As a solution to these problems, semiconductor light-emitting elements are placed on a submount substrate and sealed with a sealant, and then a groove is formed in a portion between adjoining ones of the semiconductor light-emitting elements. The grooves formed are filled with a reflective material, and a light-emitting surface is polished. Then, the submount substrate is divided into individual semiconductor light-emitting devices. Thus, a semiconductor light-emitting device having a reflective layer on its side surfaces can be obtained.