Most cases of colonic diverticular bleeding stop spontaneously, but some patients experience massive bleeding that requires emergency treatment. Endoscopy can be useful when the bleeding source is identified. However, bleeding sometimes recurs within a short period despite the successful endoscopic treatment. Under such conditions, more invasive therapy such as interventional angiography or surgery is required and can prolong hospitalization and involve frequent blood transfusions. We report the case of a 68-year-old woman who presented with massive hematochezia. The patient was in hemorrhagic shock and required 16 units of blood transfusion to recover to general condition. We performed multidetector row computed tomography, but it showed no sites of bleeding. We conducted colonoscopy and identified the source of bleeding as colonic diverticula. We treated the bleeding with endoscopic hemoclips and achieved hemostasis, but bleeding recurred the next day. Four units of blood transfusion were required. We tried high-dose barium impaction therapy to avoid further blood transfusion and surgery. No complications or recurrent bleeding was observed for an 18-month period. Therapeutic barium enema is an option for colonic diverticular bleeding unresponsive to endoscopic clipping and may be effective for preventing recurrent bleeding.