BACKGROUND AND AIM: Studies on the characteristics of elderly-onset ulcerative colitis (EOUC) and non-elderly-onset ulcerative colitis (NEOUC) have reported conflicting findings. The aim of this study was to compare disease characteristics of EOUC and NEOUC by analyzing the database of the Japanese nationwide inflammatory bowel disease (IBD) registry. METHODS: We analyzed the age of disease onset, sex, disease severity, and disease extent in patients with ulcerative colitis that were newly diagnosed and registered within 1 year between 2004 and 2009 (n = 28 179). We also analyzed the medical treatment, rate of IBD-related surgery, and postoperative complications. We compared them between younger than 65 years old (NEOUC group) and 65 years old or older (EOUC group) patients. RESULTS: A total of 25 401 (90.1%) and 2778 (9.9%) patients were included in the NEOUC and EOUC groups, respectively. In the EOUC group, disease activity was significantly higher, and extent of pathological changes in the colon more extended significantly. Laboratory findings showed that inflammatory markers were elevated significantly in the EOUC group. The proportion of those with IBD-related hospitalization was significantly higher in the EOUC group (54.2% vs 35.7%, P < 0.001). The proportion of patients who were treated with corticosteroids was significantly higher in the EOUC group (36.7% vs 30.8%, P < 0.001). Significantly more number of patients underwent IBD-related surgery in the EOUC group (0.68% vs 0.27%, P < 0.001). CONCLUSION: Elderly patients show higher disease activity, with a higher proportion requiring IBD-related hospitalization and IBD-related surgery, according to the nationwide registry in Japan.