UNLABELLED: Obstructive sleep apnea (OSA) caused by enlarged tonsils and adenoids is common in pediatric population. The prevalence of pediatric obstructive sleep apnea syndrome has been estimated to be between 1% and 3% in preschool and school-aged children. The aim of this study was to examine quality of life in children before and after adenotonsillectomy. SUBJECTS AND METHODS: This study was prospective and it was carried out in the period from mid-November 2005 to end-June 2006. Specific exclusion criteria were: no existing of OSA, neuromuscular disorders, constitutional maxillofacial anomalies, septal deviation, mental retardation, obesity (BMI > 30). Anamnesis was taken from parents or caregiver, each child was examined from ENT specialist, Pediatar and Anestesiolog. The adenoid size was estimated by palpation or/and X-ray examination of nasopharynx. The tonsils size was estimated by Brodsky scala. OSA-18 quality of life survey was used to estimate improvement of quality of life after adenotonsillectomy. The children that had asserted symptoms of OSA by OSA-18 quality of life survey, were analyzed by this survey 5 weeks after surgery. The results before and after surgery were compared. The adenotonsillectomy was done with standard operation technique at our ENT department (cold dissection using termocauter), and comprehends removal palatinal tonsils and adenoids, that are removed by adenotom with uniform anestesiology protocol. RESULTS: At 13 patients (43.3%) undergone adenotonsillectomy, OSA had a small impact on quality of life, at 11 (36.7) patients had a moderate impact and at 6 (20%) patients had large impact. Statistical significant improvement of quality of life after adenotonsillectomy was found in all domains using OSA-18-QOL survey: sleep disturbance (P < 0.0001), physical suffering (P < 0.0001), emotional distress (P < 0.0001), daytime problems (P = 0.0081) and caregiver concerns (P < 0.0001). The mean OSA-18-QOL total change score showed significant improvement of quality of life in patients suffering from OSA who undergone adenotonsillectomy. CONCLUSION: Adenotonsillectomy improves quality of life in children suffering from OSA caused by adenotonsillar hypertrophy.