One third of a person’s life is spent in sleep, and sleep is very important to everyone. Children, especially infants and young children, are still in the developmental stage of the brain, and adequate sleep can ensure growth and development. Children sleep longer than adults, and the length of sleep varies at different ages. According to the Sleep Guidelines of the American Academy of Sleep Medicine, the optimal healthy sleep time for children aged 0-18 years old (counting 24 hours a day) is as follows: 1. 4-12 months old infants: 12-16h (including naps). 2. 1-3 years old children: 11-14h (including naps). 3. 3-5 years old children: 10-13h (including naps). 4. 6-12 years old children: 9-12h. 5. 3-18 years old adolescents: 8-13h (including naps). 6-12 years old children: 9-12h. 6. 6-12 years old children: 9-13h. 7. Adolescents aged 3-18: 8-10h. The younger the age, the longer the sleep time, and the average sleep time of newborns is about 18-20 hours or more per day. Each child has different genes, personality, family environment and other factors, some sleep more, some sleep less, very normal. However, if the sleep is insufficient and the quality of sleep is poor, it is easy to have inattention, behavioral and learning problems, and even affects the child’s growth and development, such as affecting the height. Therefore, parents should pay attention to their children’s sleep, form good sleep habits, not stay up late, and have a regular routine.