The pain after defecation may be anal fissure or too spicy diet. Anal fissure is a small ulcer formed after cracking the skin layer of the anal canal under the dentate line, which often manifests itself as intense burning or cutting pain in the anus during defecation, accompanied by constipation and bleeding, relieved after defecation, and is cyclical in nature, and is mostly seen in middle-aged and young people. Most anal fissures are located in the posterior midline of the anal canal, or in the anterior midline. If the fissure appears laterally, the possibility of other diseases such as inflammatory bowel disease (e.g., tuberculosis, ulcerative colitis, and Crohn’s disease) or tumors should be considered. The etiology of anal fissure is unclear and may be related to a variety of factors, most of which are mechanical trauma caused by prolonged constipation, dry stool defecation, in addition to diarrhea is also an important cause of anal fissure formation. Acute or first attack of anal fissure patients can sit in the bath, laxative treatment; chronic anal fissure patients can sit in the bath, lubricate the stool, expanding the anus to relieve pain and promote local healing; after a long time, the above treatment is ineffective, the symptoms of the more serious people can be used for surgical treatment, such as fissure resection. The above treatments should be carried out under the guidance of professional physicians. In addition, if the diet is too spicy, it may stimulate the anus, and the subjective feeling is “hot and spicy”, at this time, we should have a light diet and drink more water.