A laser light source module includes: a plate-shaped stem; a power supply lead pin having an upper end protruding from an upper surface being one of main surfaces of the stem and a lower end penetrating to extend toward a lower surface side, the lower surface being the other of the main surface of the stem; a block fixed to the upper surface of the stem; a submount substrate that is fixed to a surface of the block and includes the semiconductor laser array mounted thereon, the surface being parallel to the upper surface of the stem; the semiconductor laser array located on the submount substrate such that a light emitting direction is parallel to the upper surface of the stem; and a collimator lens array that is located on a front surface of the semiconductor laser array and converts an output light beam of the semiconductor laser array into a parallel light beam.