To obtain a laser light source module, a copper-based material is press-fitted into a through hole formed in a stem made of an iron-based material, thereby forming a first heat sink. A mount made of a copper-based material is fixed to the first heat sink and at least one semiconductor laser device is mounted on the mount. A second heat sink is bonded to lower surfaces of the stem and the first heat sink by a thermal conductive adhesive. An upper surface of the first heat sink is located on a same plane as that of the stem, and a lower surface of the first heat sink is located higher than that of the stem.