The clinical diagnosis of functional constipation in infants and young children can be made based on history and physical examination. It occurs in 3 stages: (1) Infancy: stools become hard after the transition from breastfeeding to formula or the addition of solid supplements. (2) Early childhood: when bowel training is requested, they try to control the bowel movement but find it painful. (3) Kindergarten stage: they do not like to defecate in school. Forced rectal fingering in functional constipation can cause intense fear and adverse behavioral reactions in sick children. Treatment of functional constipation in children Treatment aim: laxative. Softening the texture of stool, relieving the discomfort caused by constipation, restoring the normal operation and emptying of the intestine, and establishing normal defecation pattern and defecation behavior. 1.Basic treatment 2.Pharmaceutical treatment 3.Psycho-behavioral therapy 4.Biofeedback treatment Basic treatment Therapeutic effect, preventive effect, prevention of relapse after stopping medication Reasonable diet: increase the intake of dietary fiber (fruits, vegetables and coarse grains) and reach a certain amount; sufficient amount of water: adults need to drink an additional 1500ml of water daily; increase the amount of activity: less computer games, less TV. Defecation habit training: develop the habit of regular daily defecation to establish a normal defecation pattern; family education Functional constipation is a very common problem in pediatrics and can be treated safely and effectively, but it takes time. Functional constipation is not life-threatening, and it is important to allay their concerns and give them confidence in the treatment. Premature bowel training does not necessarily result in earlier bowel control. It is important to stop bowel training until the fear of painful bowel movements disappears and the person is willing to perform bowel training. Empty the rectum in a timely manner to ensure painless bowel movements.