To provide an optical head and an optical disc device, in which a cover member for radiating and protecting the optical head and a laser light source are of a simple construction, manufacturing efficiency can be increased, and accuracy variation due to assembly of the laser light source such as an optical axis or the like of a laser beam can be suppressed. Therefore, a boss formed on a light source installation portion of a base is engaged with a boss hole formed on a laser light source supporting portion of the cover member, thereby positioning the cover member on the base. In doing so, an internal thread hole formed on the bottom surface of the base is overlapped with a thread hole formed on a cover portion of the cover member. In this state, a bolt is passed through the thread hole to screw in the internal thread hole.