Vallecular cysts are rarely seen in adults and occur as a result of the tongue base mucus retention. In cases with laryngeal inlet obstruction due to a vallecular cyst, the airway management sometimes might be a challenge. We presented the airway management of an adult patient with difficult airway due to a large vallecular cyst. A 28-year-old male patient with a large vallecular cyst was scheduled for surgical excision of the cyst under general anesthesia. Despite the use of different laryngoscopic blades, no laryngeal structure was seen due to the cystic formation. After aspiration of approximately 20 mL cyst content, the peripheral side of the epiglottis was seen on the left-upper side of the shrunken cyst. Therefore, laryngoscopy was performed by an insertion of the left side of the mouth, and tracheal intubation was achieved by endotracheal tube which was advanced blindly under the epiglottis. A week later, due to cyst reoccurrence, the patient was undergone surgery again. No problem arose during the course of anesthesia, surgical intervention and the postoperative period, and the patient was discharged on the fifth postoperative day. We concluded that the view of the glottis or other laryngeal structures can be obtained by shrinking the vallecular cyst size.