Anal fissure is a very common benign disease of the rectum and anal canal. The cause of anal fissure is mainly due to constipation, which causes the feces to stay in the colon cavity for too long, and the water is fully absorbed, causing the feces to be too dry, and when defecating, the dry fecal matter damages the mucous membrane of the rectum and anal canal, resulting in the formation of the disease. For the treatment of anal fissure, in general, the acute stage mainly adopts conservative treatment, eat more vegetables, fruits and other high-fiber food, can take lactulose to soften the stool, regularly expand the anus, local 1:5000 potassium permanganate sitz bath, generally 1-2 weeks can get the symptoms of relief and cure. If the effect of conservative treatment is not good, and it becomes chronic, it is usually prolonged and requires surgical treatment to get cured. For superficial anal fissure, anal fissure excision can be used, for deeper anal fissure, even need to perform anal sphincter cut off in order to get cured.