PURPOSE: Treatment for malignant colonic obstruction consists of a multiple-staged emergency operation. In recent years, some authors have reported low morbidity and mortality rates using self-expandable metallic stents. This study is designed to evaluate the usefulness of self-expandable metallic stents in patients with malignant colonic obstruction. METHODS: The records of 38 patients who had undergone surgery for malignant colonic obstruction at our institution between January 2004 and August 2006 were reviewed retrospectively. Seventeen patients were treated with elective surgery after stent insertion, bowel decompression, and bowel preparation (stent group), and 21 patients were treated with emergency surgery without stent insertion (control group). RESULTS: There were no significant differences in age, sex, tumor node metastasis (TNM) stage, or cancer position between the two groups (elective operation after stent insertion vs. emergency operation). Of the 17 patients who underwent elective operation after stent insertion, primary anastomosis was possible in 15 (88.2 vs. 57.1% in the control group), with a lower need for a colostomy (11.8 vs. 42.9% in the control group, P=0.036). Also, the number of patients with severe complications (17.6 vs. 47.6% in the control group, P=0.048) and the hospital stay (10.82 vs. 13.43 days in the control group, P=0.032) were significantly lower in the study group. CONCLUSION: Placement of a self-expandable metallic stent for malignant colonic obstruction is a safe and effective procedure. It can reduce the colostomy, mortality, and morbidity rates and the hospital fee for treatment.