Anal pain in the clinic includes the following causes: first, there may be a perianal abscess of the rectum and anus with concurrent infection. When this occurs, it often manifests itself as local redness, swelling, or even a mass, and the pain is more intense. Especially when the abscess formation is relatively large, there may be accompanied by general fever, as well as nausea, vomiting and other corresponding symptoms. Secondly, it may also be due to the formation of anal fissures or small fissures near the anus, which produce inflammatory infection under the repeated stimulation of constipation and cause pain. Third, malignant tumors of the rectum and anal canal, including rectal cancer. If it invades the soft tissue near the rectum and anus, it may also cause pain at the anus. In short, pain at the anus must not be ignored, and should actively go to the hospital to do the relevant colonoscopy, CT or doctor’s rectal examination to further find the cause of anal pain.