The combinational effect of oral corticosteroid and mizoribine for ulcerative colitis is presented in a patient with systemic sclerosis (SSc). A 64-year-old woman came to our clinic complaining of a 30-year history of Raynaud’s phenomenon. She had past history of ulcerative colitis with the continued medication of mesalazine without success. She was presented with sclerodactyly and finger joint swelling. She also showed epigastric discomfort. Laboratory study showed positive anti-nuclear antibody and positive anti-centromere antibody. Histological examination showed mild perivascular mononuclear cell infiltrates in the whole dermis and increased deposition of collagen fibers in the middle and lower dermis. Chest X-ray film showed mild bibasilar pulmonary fibrosis. An upper gastrointestinal series study showed reflux esophagitis and atrophic gastritis. These findings led to the diagnosis of systemic sclerosis (limited type) complicated with ulcerative colitis. Treatment with oral corticosteroid (5 mg/day) and mizoribine (150 mg/day) in the morning was started. She showed remarkable improvement for sclerodactyly and lower intestinal bleeding stopped after 6 months. She is under the same treatment without exaggeration and adverse effect of the drug until now.