ABSTRACT The human upper airway is important in many voluntary and involuntary tasks such as swallowing, speech and breathing. The nasal, pharyngeal and laryngeal region forms upper airway. It is a complicated structure that plays a key role in breathing, vocalization and swallowing. The upper airway is a highly flexible structure that lack rigid bony support. It is vulnerable by pressures that are generated during inspiration and by the surrounding soft tissues. The focus in this article was on the genioglossus muscle and its role in maintaining upper airway.