There are many causes of pediatric blood in the stool, including anal fissures, which are more likely to be overlooked by parents. If fissures are not treated in a timely manner, they often become infected, forming paranal abscesses and possibly fistulas, which can increase the pain of the child. Anal fissures are usually caused by constipation. Why does constipation occur in children? First, there is no regular bowel habits. Some parents do not pay attention to arranging regular bowel movements for their children, and do not develop regular bowel habits, plus the ability of children to tolerate bowel movements is very strong, so that each bowel movement is separated by a long time, which can easily lead to constipation. Second, the amount of activity is too little. Children are either lying down, or being held, rarely do prone or crawling activities, and often pushed by the car when going out, lack of opportunities for activity. Because the total amount of activity is too little, thus reducing the peristaltic function of the intestine, become one of the factors of pediatric constipation. Third, the food is too fine. Some children eat too much milk, eggs, chocolate, pastries, etc., and eat less coarse grains, vegetables, fruits, etc.. Due to too little fiber in the food, also easy to lead to pediatric constipation. After a child has constipation, fissure and blood in the stool, many parents treat the symptoms but not the root cause, relying solely on the use of laxatives, or even glycerin suppositories, soap bars into the child’s anus to laxative, which can solve the urgent defecation difficulties, but the child has developed a harmful habit of relying on auxiliary methods to defecate, resulting in constipation, fissure and blood in the stool become increasingly serious. In order to effectively prevent pediatric anal fissures, parents should pay attention to cultivating regular bowel habits in children, increasing the amount of appropriate exercise for children, such as allowing infants to do more prone and crawling exercises, and more walking for children over the age of one year; implementing scientific feeding, especially to allow children to eat a sufficient amount of vegetables every day, small infants can drink boiled vegetable soup or eat a small amount of vegetable puree.