Pediatric OSA affects 1 to 3% of the population and appears to affect boys and girls equally [4]. The most commonly cause of pediatric OSA is adenotonsillar hypertrophy. Thus, the primary treatment is adenotonsillectomy. Pediatric OSA has been associated with some psychological problems, of which neurocognitive and depression , difficulties particularly in memory , attention, learning and executive function, are the most widely reported. The neurocognitive deficits is due to the adverse effects of sleep fragmentation and/or intermittent hypoxia .Scholastic performance have been reported in little studies of pediatric OSA, and such findings may underscore more extensive behavioral disturbances such as restlessness, aggressive behavior, excessive daytime sleepiness and poor test performances. The aim of this study was to evaluate the effect of adenotonsillectomy (AT), in children with Obstructive Sleep Apnea (OSA), on the cognitive and scholastic achievement.