A semiconductor laser device of the present invention is provided with a base portion (2) having a horizontal top surface (S), a heat sink portion (3) that has a vertical element mount surface (7) and is located above the top surface (S) of the base portion (2), and a semiconductor laser element (4) that is fixed to the element mount surface (7). There is formed a depression (9) in the base portion (2) located immediately below the semiconductor laser element (4) so as to receive part of the semiconductor laser element (4) disposed in the depression (9). The element mount surface (7) is located inward of the inner side surface of the depression (9).