Various circulating auto-antibodies have been reported in patients with ulcerative colitis. Hepatoma-derived growth factor (HDGF) is a mitogen, localized dominantly in the nucleus of proliferating cells. In this study, we demonstrated the circulating anti-HDGF auto-antibody and investigated its clinical roles in patients with ulcerative colitis. Anti-HDGF IgG antibodies were measured by the enzyme-linked immunosorbent assay with recombinant HDGF in 20 healthy volunteers and 40 patients with ulcerative colitis. Circulating anti-HDGF antibody was detected in the serum of a patient with total colitis by Western blotting. Anti-HDGF auto-antibodies were detected at 65.6% in the serum of patients with total/left-sided colitis, compared with healthy subjects at 10%. During active stage, the circulating anti-HDGF auto-antibodies were detected at a higher frequency of 78.3% than those in remission stage at 37.5%. Furthermore, the titers during active colitis were higher than those during the remission stage. Anti-HDGF auto-antibodies were not detected in any patients with proctitis. These findings suggest that anti-HDGF auto-antibodies in the serum of patients with ulcerative colitis would help to classify the total/left-sided colitis from proctitis, and the serial measurement of the titer would also be a good marker for the active colitis.