Twenty-three adults with moderate to severe sleep apnea syndrome (SAS) and positive ENT obstructive findings were treated by either tonsillectomy or by submucosal resection (SMR). Fourteen of the 23 patients (60.8%), 5 of the 7 who underwent tonsillectomy and 9 of the 16 treated by SMR, reported on a clinical improvement in the quality of their nocturnal sleep and diurnal hypersomnolence. Post-treatment polyhypnographic recordings in all responding patients disclosed significantly less apneas and waking within sleep.