The present disclosure provides a laser diode package module. The laser diode package module includes a substrate including a first surface; a cover disposed on the first surface of the substrate; an accommodation space formed between the substrate and the cover; a laser diode die disposed in the accommodation space; and a reflective surface disposed in the accommodation space for outputting light of the laser diode die reflected by the reflective surface and transmitted through a light-transmitting area. The light-transmitting area is at least partially disposed on a surface of the cover opposite the substrate.