Background: Gastrointestinal (GI) cytomegaloviral (CMV) infection is common among patients with immunocompromised status; however, data specific to GI-CMV infection in immunocompetent patients are comparatively limited.Methods: This retrospective study included patients diagnosed with GI-CMV infection at Siriraj Hospital (Bangkok, Thailand) during 2008-2017. Baseline characteristics, presentations, comorbid conditions, endoscopic findings, treatments, and outcomes were compared between immunocompetent and immunocompromised.Results: One hundred and seventy-three patients (56 immunocompetent, 117 immunocompromised) were included. Immunocompetent patients were significantly older than immunocompromised patients (73 vs. 48.6 years, p < 0.0001). Significantly more immunocompetent patients were in the ICU at the time of diagnosis (21.0% vs. 8.6%, p = 0.024). GI bleeding was the leading presentation in immunocompetent, while diarrhea and abdominal pain were more common in immunocompromised. Blood CMV viral load was negative in significantly more immunocompetent than immunocompromised (40.7% vs. 12.9%, p = 0.002). Ganciclovir was the main treatment in both groups. Significantly more immunocompetent than immunocompromised did not receive any specific therapy (25.5% vs. 4.4%, p ≤ 0.01). Six-month mortality was significantly higher among immunocompetent patients (39.0% vs. 22.0%, p = 0.047). Independent predictors of death were old age and inpatient or ICU clinical setting. Treatment with antiviral agents was the only independent protective factor. Conclusion: GI-CMV infection was frequently observed among immunocompetent elderly patients with comorbidities or severe concomitant illnesses. GI bleeding was the most common presentation. Blood CMV viral load was not diagnostically helpful. Significantly higher mortality was observed in immunocompetent than in immunocompromised patients, but this could be due to more severe concomitant illnesses in the immunocompetent group.