Few new therapies for pediatric obstructive sleep apnea syndrome (OSAS) have been validated with randomized controlled trials. Based on the current evidence, it is cruial to achieve early diagnosis and provide definitive therapy of this condition. This review provides an update review of epidemiology, clinical features, complications, and treatment of childhood OSAS and the benefit of tonsillectomy for children who have obstructed apneas, constant snoring and difficult breathing during sleep. The concise indications for adeno-tonsillectomy are children over three years of age with OSAS and also those children who have three or more tonsil infections in one year.