OBJECTIVES: We evaluated the clinical significance of adenoidal vegetations which are overlooked as a cause of nasal obstruction in adults. PATIENTS AND METHODS: The study included 12 patients older than 15 years of age (10 males, 2 females; mean age 23.5 years; range 15 to 32 years) who presented with nasal obstruction due to adenoidal vegetations. The patients were evaluated with respect to age, sex, complaints, findings of physical examination, computed tomography of the nasopharynx, and nasal endoscopy, and histopathologic results. RESULTS: All the patients had nasal obstruction. The most common symptom was snoring. Physical examination showed a vegetative mass in the posterior wall of the nasopharynx obstructing the choana. Five patients had bilateral serous otitis media and eight patients had postnasal purulent drainage. All the patients underwent adenoidectomy under general anesthesia and with transnasal endoscopic control. Histopathologic examination of surgical specimens showed lymphoid hyperplasia. CONCLUSION: Although adenoidal tissue undergoes regression toward the adolescent period, it may present as the chief cause of nasal obstruction in adults.