We report our findings and results on treating a patient with Fournier’s gangrene by using colostomy along with open drainage. A 39-year-old male had noticed a swelling and experienced pain in the scrotal sac approximately 1 week before his admission. On admission, his symptoms aggravated and he experienced constipation and difficulty in urination. Local examination of the scrotum circumference revealed a remarkable swelling, and redness and sloughing that had extended to the perianal area. In an emergency operation, incision and drainage of the scrotum, double-barrelled colostomy at the transverse colon, and reconstruction of the percutaneous cystotomy were performed. Postoperative open wound was cleaned twice a day and intravenous infusions of 1g imipenem/cilastatin sodium and 1.2g clindamycin phosphate were administered daily. The patient was discharged 61 days after the operation. Fournier’s gangrene has a high mortality rate, and in severe cases that are complicated with infection protracted from defecation, dyschezia and difficulty in urination, we believe that it would be most effective to perform an open drainage and a colostomy simultaneously.