Objective. To study characteristics of sleep structure based on polysomnography (PSG) data of intellectually gifted schoolchildren. Material and methods. Forty-four 8—9 grade schoolchildren of the boarding school were examined. In the first stage, the level of intellectual development was assessed with Raven’s Progressive Matrices. An analysis of medical history and clinical examination were performed as well. Based on the result of testing, the adolescents were divided into medium intelligence group (n=15) and high intelligence group (n=29). The second stage included PSG examination. Results and conclusion. There was a trend towards an increase in sleep latency with a significant decrease of deep sleep, a significant decrease in REM-sleep latency and an increase in the number of REM-sleep episodes in the high intelligence group. No significant differences in waking after sleep onset, number of arousals (EEG activations) and respiratory events, and oxygen saturation levels were identified. The characteristics of PSG in intellectually gifted schoolchildren should be considered as a compensatory and adaptive reaction in response to constant increased intellectual loads and stressful situations as risk factors for psychosomatic disorders.