PURPOSE: Stoma formation has usually been used for bowel decompression or fecal diversion. For these, a cecostomy is rarely performed because of disadvantages such as incomplete fecal diversion or fatal complications. The aim of this study was to evaluate the usefulness of an open cecostomy in treating patients with colonic obstruction. METHODS: Between May 2005 and August 2008, 20 patients underwent an open cecostomy because of colonic obstruction. All information on the patients was reviewed retrospectively for underlying disease, obstruction site, diameter of the cecum and transverse colon, and complications. RESULTS: Of the 20 patients, 14 had colorectal cancer, 3 had stomach cancer, 1 had cervical cancer, 1 had a carcinoid tumor, and 1 had an osteosarcoma. The cause of the obstruction was the primary tumor in 7 patients, peritoneal carcinomatosis in 7 patients, local recurrence in 5, and tissue edema after cyberknife treatment in 1 patient. All patients, except for 1 patient with a hopeless discharge due to rapid disease progression, were discharged on the tenth day postoperatively. No fatal complication developed. In 2 patients, the cecostomy closed spontaneously at 5.5 mo postoperatively after the distal obstruction had been resolved. CONCLUSION: An open cecostomy may be a useful and simple method for the decompression of a colonic obstruction, even though the diversion may not be complete.