Anal discomfort after defecation can be considered to be related to various diseases such as ulcerative colitis, rectal prolapse, perirectal abscess or rectal cancer. 1. Ulcerative colitis: inflammatory lesions occurring in the colon and rectum, commonly found in the rectum and sigmoid colon, with abdominal pain, diarrhea, mucus, pus and blood stools, due to the involvement of the rectum can be manifested as a sense of urgency and heaviness, and a sense of incomplete evacuation after defecation. 2. Rectal prolapse: due to anatomical factors or increased abdominal pressure, the rectal mucosa can be prolapsed from the anus. With the increase of prolapse volume, it is necessary to hold it back by hand after defecation, which can be accompanied by a feeling of falling and incomplete defecation. 3. Peri-rectal abscess: such as pelvic rectal gap abscess, which can be caused by rectal trauma, proctitis, etc., with localized feeling of incomplete bowel movement, discomfort during defecation and sensation of rectal swelling, and perianal discomfort. 4. Rectal cancer: there is no obvious symptom in the early stage, if the cancer stimulates the rectum, it can cause change of defecation habit, feeling of dropping in the anus, feeling of urgency and feeling of incomplete defecation. If there is anal discomfort after defecation, it is recommended to consult doctor in time, improve anal diagnosis or endoscopy and other related examinations to clarify the cause of the disease, and then give treatment according to the cause and symptoms to avoid delaying the aggravation of the disease.