A total of sixty one patients with carcinoma of the rectum accepted radiotherapy of 40 Gy/4W to whole pelvis including the perineum. Randomized study of preoperative radiation to the pelvis showed that patients with advanced carcinoma of the lower rectum and the anus benefited in the prevention of the local recurrence and in the curability of unresectable tumor. Postoperative radiation therapy was indicated in the case of the residual tumor, metastatic lymphnodes, distinct lymphatic permeation and insufficient excision of the rectum. For the pelvic recurrence irradiation of doses more than 36 Gy was effective in the case of slow growing tumor. A radical treatment is expected for patients with inoperable tumor or for patients without indication of major surgery because of age or medical problems by the whole pelvic irradiation plus interstitial irradiation.