A semiconductor laser device includes a heat sink, a submount, a first electrode, an insulating layer, a semiconductor laser element, a connecting portion, and a second electrode. The submount is conductive and on a first region of an upper surface of the heat sink. The first electrode is conductive and on a second region, different from the first region, of the upper surface of the heat sink. The first electrode is electrically connected either to at least part of a side surface of the submount or to an upper surface of the submount.