We have experienced 471 patients with anal bleeding during the past seven years. The Results are as follows: 1. As for the types of disease, incidence of hemorrhoid, colorectal cancer and ulcerative colitis (UC) was high, while that of small intestinal problems was low. 2. In the cases of remarkable bleeding from the lower intestinal tract, massive or acute progressive bleeding was less frequent than expected. 3. Inflammatory diseases were the main causes of massive bleeding. Bleeding by UC was the major indication for urgent operation. In the cases with acute massive hemorrhage, basic complications were often found and the possibility of the diseases of small intestine and blood vessel disorders also should be considered. 4. At the examination of bleeding patients, it is efficient to explore the lower colon and rectum first by colonoscopy or sigmoidoscopy, for most of the bleeding lesions are found in these portions. 5. As for surgical treatment, most of colorectal cancer patients with hemorrhage are able to be operated with wait- and -see management. For UC patients, complete cure operation is possible even if they have high-dose steroid medication.