The best time of the day to sleep is from 23:00 at night to 7:00 the next morning, with 8 hours of sleep, but adolescents should have 10 hours of sleep because of the need to grow their bodies. Deep sleep should be more than 4 hours and light sleep should be less than 3 hours. It takes about 3 hours to enter the deep sleep phase from sleep, sleep at 23:00 and enter the deep sleep phase at 2-3:00 a.m. This time can make the brain cells get enough rest, eliminate fatigue, increase human memory, reduce plant nerve dysfunction, repair and improve cardiovascular endothelial cells and blood supply system, and also help to release growth hormone and promote adolescent body growth. It is recommended to sleep on time, get up on time, and develop a good work and rest schedule. Irregularity in life can lead to insomnia, and insomnia can lead to many diseases, the most common clinical memory loss and physical subhealth.