A method of fabricating a semiconductor light-emitting device includes: (a) forming a semiconductor layer including a light-emitting layer on the first surface of a substrate; (b) forming a first trench and a second trench in the semiconductor layer, the first trench extending in a first direction that is parallel to a principal plane of the substrate, and the second trench being disposed inside and parallel to the first trench; (c) forming a third trench parallel to the first trench in the second surface of the substrate opposite to the first surface of the substrate; and (d) forming a semiconductor light-emitting device by dividing the substrate. In (d), an end of at least one divided side of the semiconductor light-emitting device is in the second trench. The first trench has a first width, and the second trench has a second width. The second width is less than the first width.