Provided is a method of fabricating a laser diode. Embodiments of the method include sequentially forming at least a lower clad layer, a resonance layer, an upper clad layer, an upper contact layer, an upper electrode layer, and a sacrificial layer on a substrate; forming a ridge portion by etching the sacrificial layer, the upper electrode layer, the upper contact layer, and a predetermined depth of the upper clad layer; exposing both top surfaces of the upper contact layer and both bottom surfaces of the sacrificial layer corresponding thereto by etching portions of the upper electrode layer, which are exposed on both sides of the ridge portion; forming a buried layer having an opening that exposes at least a portion of the bottom surface of the sacrificial layer, the buried layer formed on the surface of the ridge portion and the top surface of the upper clad layer that extends from the ridge portion; and removing the sacrificial layer and a portion of the buried layer disposed thereon by supplying an etchant through the opening.