Background: Although isolated terminal ileal ulcerations (ITIUs) are occasionally observed on colonoscopic examination of asymptomatic individuals, their clinical course and guidelines for treatment are unclear. Objective: To evaluate the clinical course and significance of ITIUs in asymptomatic individuals. Design: Single-center retrospective analysis. Setting: University hospital. Patients and Interventions: All patients diagnosed with ITIUs on colonoscopy from July 2001 to December 2007 were identified. Patients with colorectal symptoms, a history of nonsteroidal anti-inflammatory drug consumption, a history of colorectal surgery, oral or genital ulcerations, and coincidental ulceration in the ileocecal valve or colon were excluded. Main Outcome Measurements: Colonoscopic findings and clinical courses of patients were analyzed. Results: Of the 148 included patients, 93 were followed (mean duration, 29.9 months). Of these, 62 showed resolution of ITIU on follow-up colonoscopy, including 60 who resolved without any treatment and 2 who resolved after antituberculosis medication. Follow-up colonoscopy continued to show ITIUs in the remaining 31 patients, only 1 of whom developed typical Crohn's disease, whereas the other 30 showed no significant changes in the lesions (n = 22), partial improvement (n = 6), or waxing and waning endoscopic appearance (n = 2). Limitations: Retrospective design, relatively short-term follow-up. Conclusions: Most ITIUs incidentally observed in asymptomatic individuals resolve without any treatment. Even if these lesions persist, it is unusual for them to progress or to cause any symptoms. (Gastrointest Endose 2010;72:1226-32.)