Ulcerative colitis is a chronic inflammatory bowel disease of unknown etiopathogenesis and increasing incidence in recent years. Perianal complications of ulcerative colitis are rare and seem to be associated with higher extent of inflammation and a more severe course of the disease. The cases of two male patients with severe corticoid-dependent ulcerative colitis of protracted clinical course who developed perianal fistulas and abscesses successfully treated with infliximab are reported. Treatment with infliximab was followed by perianal fistula closure with marked improvement in the quality of life over 2-year follow-up period.