Genioglossus is one of the muscles of the tongue. It arises as a narrow, short tendon from the superior mental process on the posterior surface of the mandible. It fans out widely both posteriorly and superiorly. It inserts into the dorsum of the tongue along most of its length. Also, the most inferior fibres insert into the hyoid bone.
Genioglossus is innervated by the hypoglossal nerve (CN XII).
It acts to both protract and depress the tongue.