A semiconductor laser device (100), characterized in that it has, as its well layer, a III-V compound semiconductor layer (106) comprising nitrogen, antimony and one or more V Group elements except nitrogen and antimony as the V Group components thereof; and a method for crystal growth for forming the III-V compound semiconductor layer, characterized in that it comprises a step comprising supplying a plurality of materials including indium simultaneously and a step comprising supplying a plurality of materials including antimony and excluding indium simultaneously, and the two steps are repeatedly carried out.