In a laser light source module, a light source disposed on a base with a temperature adjusting element therebetween is covered by an inner cover, and is hermetically sealed by an outer cover. A top plate of the inner cover divides the inside of the outer cover into upper and lower sections and covers the light source from above. Side plates cover the side portions of the light source. Partitioning grid plates are provided in a space between the top plate and the outer cover, the partitioning grid plates dividing the space into multiple spaces.