A method of manufacturing a light emitting device, the method comprising: disposing a first semiconductor laser element on a disposition surface of a base member such that a light emission end surface of the first semiconductor laser element is parallel to a first line passing through a pair of alignment marks (181, 182) provided on the base member; and disposing a first light-reflective member on the disposition surface such that a reference line for the first light-reflective member, which serves as an alignment reference in disposing the first light-reflective member, is parallel to a second line that is oblique to the first line at a predetermined angle; characterized in that the method further comprises: disposing a second semiconductor laser element on the disposition surface such that a light emission end surface of the second semiconductor laser element is parallel to the first line, and such that the first semiconductor laser element and the second semiconductor laser element are disposed symmetrically to each other with reference to a midpoint of the first line between the alignment marks (181, 182); and disposing a second light-reflective member on the disposition surface such that a reference line for the second light-reflective member is parallel to the second line, and such that the first light-reflective member and the second light-reflective member are disposed symmetrically to each other with reference to the midpoint of the first line. disposing a first semiconductor laser element on a disposition surface of a base member such that a light emission end surface of the first semiconductor laser element is parallel to a first line passing through a pair of alignment marks (181, 182) provided on the base member; and disposing a first light-reflective member on the disposition surface such that a reference line for the first light-reflective member, which serves as an alignment reference in disposing the first light-reflective member, is parallel to a second line that is oblique to the first line at a predetermined angle; characterized in that the method further comprises: disposing a second semiconductor laser element on the disposition surface such that a light emission end surface of the second semiconductor laser element is parallel to the first line, and such that the first semiconductor laser element and the second semiconductor laser element are disposed symmetrically to each other with reference to a midpoint of the first line between the alignment marks (181, 182); and disposing a second light-reflective member on the disposition surface such that a reference line for the second light-reflective member is parallel to the second line, and such that the first light-reflective member and the second light-reflective member are disposed symmetrically to each other with reference to the midpoint of the first line. disposing a second semiconductor laser element on the disposition surface such that a light emission end surface of the second semiconductor laser element is parallel to the first line, and such that the first semiconductor laser element and the second semiconductor laser element are disposed symmetrically to each other with reference to a midpoint of the first line between the alignment marks (181, 182); and disposing a second light-reflective member on the disposition surface such that a reference line for the second light-reflective member is parallel to the second line, and such that the first light-reflective member and the second light-reflective member are disposed symmetrically to each other with reference to the midpoint of the first line.