Most anal fissures are caused by chronic constipation, dry and hard stools, and excessive dilatation and tearing of the anal opening during defecation. Common manifestations: anal pain, aggravated by defecation, blood in the stool. The child is often afraid to defecate because of the fear of pain, which makes the stool accumulate and aggravate the constipation, making the stool lump harder and the pain more intense in the next defecation, resulting in a vicious cycle. The blood in the stool is fresh blood, and the amount is not large, often several drops of fresh blood appear at the end of the bowel movement. Sometimes there is only blood attached to the surface of the stool, or there is blood on the stool paper. Treatment: Conservative treatment for infants and young children with anal fissures includes treatment of constipation and local treatment: 1. adjust the dietary structure, eat more vegetables and fruits to soften the stool, take liquid paraffin oil or sesame oil if necessary, and develop regular bowel hygiene habits; 2. use local hot compresses, warm water or potassium permanganate sitz baths to reduce pain; 3. clean the fissure wound, 3-4 times a day, and apply antibiotic ointment or Chinese herbal medicine biochemical ointment, etc., to promote wound healing. If chronic anal fissure or acute anal fissure by conservative treatment does not work, go to the hospital to perform surgery.