Fournier gangrene is a very rare and a rapidly progressing, polymicrobial necrotizing faciitis or myonecrosis of the perineal, perianal and genital regions, with a high mortality rate. Infection is associated with superficial traum, urological and colorectal diseases and operations. The most commonly found bacteria are Escherichia coli followed by Bacteroides and streptococcal species. Diabetes mellitus, alcoholism, and immunosuppression are perpetuating co-factors. Fournier's gangrene complicating inflammatory bowel disease has been reported in three patients so far, two with Crohn's disease. A 78-year-old man diagnosed with ulcerative pancolitis was referred for fever, and painful perianal and scrotal swelling after perianal surgery for a horseshoe-type perianal abscess. Since bowel disease diagnosis, patient was on mesalazine and achieved long-term remission. Perianal abscess occurred suddenly one week before perianal surgery without any evidence of pre-existing fistula or other abnormalities. Physical examination showed extensive edema and crepitus of perineum and genitalia and patient had symptoms of significant toxicity. The diagnosis of Fournier's gangrene was made and patient underwent emergency surgery with extensive surgical debridement of the scrotal and perianal area and Hartman procedure with a diverting colostomy. In addition, patient started on therapy with mesalazine 3gr, methylprednisolone 16 mg, parenteral nutrition and broad spectrum of antibiotics. Two days after the first operation the patient needed a second operation for perianal debridement. On the fourth day, blood cultures showed E. coli. Patient had an uneventful recovery and was discharged after 34 days of hospitalization. On follow up, disease review is scheduled and colostomy closure is planned.