Anal fissures are prismatic fissures or ulcers formed by rupture of the skin of the anal canal below the dentate line. It is a common anal canal disease that occurs in young adults, but can also occur in children and less often in the elderly. According to statistics in Europe and the United States, women get this disease more often than men, and according to clinical observation in China, men are more common than women. Anal fissures often occur in the back and front of the anus, mostly in the back of the anus, and less in both sides. The fissure is linear or prismatic, and if the anus is opened, the fissure becomes round or oval-shaped. Anal fissures are lacerations that occur in the entire skin layer of the anal canal. The cause is mostly due to dry stools. It occurs in the posterior or anterior position of the anus. Both men and women, young and old, can suffer from this disease. The clinical symptoms of anal fissure are pain and bleeding. The pain is characteristic, i.e., it starts with a sudden cut-like pain during defecation (due to feces cutting through the skin of the anal canal), then relieves briefly, followed by prolonged anal pain (due to spasm of the anal sphincter after stimulation). Bleeding due to anal fissures is also more or less frequent depending on the extent of the torn blood vessels, and cases of anemia due to prolonged or heavy bleeding from anal fissures are common. If anal fissures are not treated in time, three conditions may occur: anal canal ulcer (fissure fibrosis, also known as old anal fissures), anal papillary hypertrophy (polypoid tumor), and sentinel hemorrhoids (dermal hyperplasia), etc. If they continue to develop, anal sinusitis (chronic inflammation of the anus) and anal fistula (purulent inflammation of the anus) may also occur. The first three are called the “five features of anal fissure”. There is also the possibility of becoming anal canal cancer due to long-term chronic inflammatory irritation. Early prevention and treatment of anal fissures should be advocated: some people have never suffered from anal fissures in their life, and their experience lies in keeping their stools soft, having a regular bowel movement on time, and not having bad habits of squatting for a long time. This is the fundamental way to prevent anal fissures. Early onset anal fissures can be completely cured by conservative treatment. For example, the use of coarse fiber diet or laxative drugs to soften the stool, with external drugs such as 2% raw skin nitrate water or hemorrhoid bath hot bath, Huanglian cream, Jiuhua cream, etc., if at the same time ask a specialist to help on the drainage strips, the recovery is faster, usually a week to cure. For chronic and recurrent anal fissures, it is advisable to perform surgical treatment or Chinese medicine. Manual treatment, i.e. anal dilation, can heal old anal fissures. The TCM surgery is divided into ligation, thread hanging and lateral incision, which are chosen by the doctor according to the condition and can cure the “five characteristics of anal fissure.”