Long-term untreated anal fissures are usually not cancerous, but there are many secondary pathologies that can occur over time, such as anal papillomegaly, connective tissue hemorrhoids, anal fistulas, and anal stenosis. Anal fissure is a common disease in anorectal medicine, mostly due to mechanical trauma to the anus caused by dry stool and difficult defecation. Anal fissures left untreated for several years are not usually cancerous, but may lead to other complications. If constipation occurs repeatedly, resulting in difficulty in healing the fissure, it may form an old anal fissure, leading to recurrent episodes of persistent anal pain and blood in the stool. The proliferation of anal papillae in the anal canal stimulated by stool can cause anal papillomegaly, anal fissure and the proliferation of perianal dermatomes, forming sentinel hemorrhoids, i.e. anal fissure triad, which seriously affects patients’ daily life and work and also increases the difficulty of treatment. Therefore, it is recommended that patients with anal fissures pay attention to adjusting their diet and keeping their bowels open in the early stages, which can sometimes heal on their own. However, if conservative treatment is ineffective, recurrent anal fissures and old anal fissures are formed, surgical treatment is required.