A small subset of patients with active ulcerative colitis is non-responsive to major known non-biological therapies.We reported 5 patients with positive serum proteinase-3 antineutrophil cytoplasmic antibody (PR3-ANCA) and tried to (1) identify the common clinical features of these patients; (2) investigate the efficacy of a novel therapy using a Chinese medicine compound; and (3) attract more gastroenterologists to be engaged in further study of this subset of patients. The common manifestations of disease in these 5 patients included recurrent bloody diarrhea and inflammatory lesions involving the entire colorectal mucosa. Initial treatment with intravenous methylprednisolone successfully induced remission.Four of these 5 patients were steroid-dependence,and immunosuppressants, such as azathioprine and cyclophosphamide, were ineffective. In 3 patients,only the particular Chinese medicine compound could induce and maintain remission. One patient underwent colectomy. No vascular inflammatory lesions were found by histopathological examination. Although more cases are needed for confirmation, our study indicates that ulcerative colitis with positive PR3-ANCA may belong to a subtype of refractory ulcerative colitis. The particular Chinese medicine compound used in our study is by far the most effective in the management of these patients,with additional advantages of having no noticeable sideeffects and less financial burden.