Rectal mucosal changes refer to inflammatory changes in the rectal mucosa or the appearance of ulcers, tumors and other changes. 1. Inflammatory changes: Rectal mucosal changes are most commonly seen in inflammatory changes, where the patient develops rectal mucosal erosion, bleeding, and edema. The problem of bloody or black stools can be observed in the stool. 2. Rectal ulcer: through proctoscopy, ulcerative changes can occur in the intestinal mucosa, and when ulcerative changes are found, pathological examination is needed to exclude the presence of malignant tumors. 3. Rectal tumors: rectal tumors, in particular, need to rule out the existence of rectal cancer, and suspicious occupying lesions need to take pathological biopsy for examination. For patients with various changes of rectal mucosa, it is suggested that they should consult the anorectal department of regular hospitals and be treated accordingly after perfect examination and clear diagnosis.