A method of manufacturing a ridge-type semiconductor laser includes the steps of forming a stacked semiconductor layer including an active layer and an etch stop layer on first and second surfaces of a substrate, etching the stacked semiconductor layer on the second surface, forming a semiconductor portion on the second surface, forming a ridge waveguide portion by etching the stacked semiconductor layer on the first surface to a first depth, forming semiconductor diffraction grating portions by etching the semiconductor portion to a second depth, and forming a diffraction grating section by providing resin diffraction grating portions between the semiconductor diffraction grating portions. The etching of the stacked semiconductor layer on the first surface and the etching of the semiconductor portion are performed simultaneously by using first and second mask portions.