Anal burning symptoms after defecation may be caused by physiological factors, and may be related to pathological factors such as constipation, hemorrhoids, anal inflammation, anal fissure, anal tumors and so on. 1. Physiological factors: such as the consumption of peppers, chili peppers, onions and other spicy stimulating food, defecation can be stimulated on the skin around the anal canal, resulting in anal burning symptoms, timely adjustment of eating habits, light diet, the symptoms can be gradually relieved after the disappearance. 2. Pathological factors (1) constipation: constipation causes dry and hard stools, hard fecal matter during defecation can produce stimulation of the anus, can also cause damage to the skin of the anal canal, resulting in burning sensation in the anus after defecation. (2) Hemorrhoids: mostly related to sedentary and other bad habits, peri venous inflammation caused by venous vascular degeneration, coupled with defecation stimulation, which can be manifested as post defecation anal burning, bleeding and other symptoms. (3) anal inflammation: anal infection with bacteria, fungi, mycoplasma, viruses, etc. can cause local inflammation, such as sinusitis, anusitis, etc., inflammation stimulation during defecation can cause burning sensation in the anus. (4) Anal fissure: it can cause small ulcers on the skin of anal canal under dentate line, and the stool can stimulate the ulcerated surface during defecation, which can cause burning, bleeding, pain and other symptoms after defecation. (5) Anal tumor: If there is anal tumor, due to long-term friction of stool, it can cause local ulcers, which can cause post-stool anal burning symptoms. After excluding the physiological factors, if the symptoms of burning sensation in anus after defecation occur, it is recommended to consult the doctor in time, improve the anorectal examination, and actively treat the cause of the disease in order to avoid delaying the condition.