There are several problems with anal pain after defecation: 1, pain caused by anal fissure: most appear during or after defecation pain is very strong, the pain will last from several minutes to several hours, sometimes until the next defecation. 2, hemorrhoids: in most of the time there is no particularly obvious pain symptoms, when defecation stool friction to hemorrhoids will lead to anal pain, the pain sometimes lasts until after the stool. The pain is particularly intense and will intensify after defecation, sometimes with fever. 4. acute attack of anal sinus: people with a history of anal sinus disease are more likely to have pain, usually or after defecation, and there will be a swollen bag at the anus, which will be particularly painful if pressed, and some people will have fever.