The subjects were composed of 308 children who visited the department of pediatrics, ${igcirc}{igcirc}$ korean medicine hospital from January 2010 to May 2013. Results 1. Among 308 patients, there were 188 boys and 120 girls; their ratio was 1.57:1. The age distribution showed that 38.3% were in the age less than 1 years, 38.0% in 1 years, 7.8% in 2 years, 5.2% in 3 years, 3.3% in 4~5 years, 4.5% in 6~10 years, 2.9% in 19~21 years. 2. It was found that 36.7% of the sleep disorder was caused without motivation, 17.2% caused by negligent accidents, 13.9% by traffic accidents, 10.4% by the unfamiliar environment, 8.1% by separation from parents, 7.5% after suffering disease, and 6.2% by irritating sound. 3. The sleep onset insomnia accounts for 17.2% of sleep disorder, sleep maintenance insomnia for 67.5%, poor sleep quality 24.4%, and daytime sleep disorder takes 19.8%. The ratio of sleep onset insomnia in adolescence comprises larger proportion (44.4%) than it of any other age groups. 4. The symptoms complicated with sleep disorder are the respiratory infection which takes 25.3%, being easily startled 18.2%, anorexia 14.6%, soft stools frequency 13.0%, greenish stools 10.7%, and skin rash 10.7%. Conclusions The causes of sleep disorders, changes of sleeping patterns, and complicated diseases show diversity in children and adolescence. Further study of sleep disorders in children and adolescence should be progressed as well.