Abstract: In a multi-beam semiconductor laser device, relative difference in shear strain applied to each of light-emitting portions of a laser chip mounted on a submount is suppressed, thereby reducing relative difference in polarization angle. A semiconductor laser element array mounted on a submount has a structure in which a semiconductor layer having two ridge portions is stacked on a substrate, and Au plating layers are formed on the surfaces of p type electrodes formed on the ridge portions. In each of the ridge portions, a central position of the Au plating layer in a width direction is intentionally displaced with respect to a central position of the underlying light-emitting portion in a width direction, so that shear strain is applied to each of the light-emitting portions at a stage before the semiconductor laser element array is mounted on the submount.