Cytomegalovirus (CMV) infection has long been recognized as an important viral syndrome in the immunocompromised host. The disease is less well described in critically-ill patients. We evaluated the risk factors for the development of CMV infection in patients admitted to the intensive care unit (ICU). We also compared the outcomes of CMV infection in ICU patients to those of patients with hematological malignancies. This is a retrospective study composed of three arms: patients admitted to the ICU with infection (ICU + / CMV + arm), patients admitted to the ICU who did not develop CMV infection (ICU + / CMV- arm, and patients with hematological malignancies on the hematology ward without CMV infection (ICU - / CMV + arm). Patients who were admitted to ICU for surgical causes had a decreased risk of CMV infection. On the other hand, receiving corticosteroids and vasoactive drugs was associated with an increased risk of CMV infection with adjusted odds ratios (aOR) of 2.4 and 25.3, respectively. Mortality was higher in ICU + / CMV + patients compared to ICU - / CMV + patients. In the ICU + /CMV + population, male sex and being on mechanical ventilation after CMV infection were independent predictors of mortality (aOR 4.6 and 5.0, respectively). CMV infection in ICU patients is a potentially serious disease requiring close attention. The findings from our study help in identifying patients in the ICU at risk for CMV infection, thereby warranting frequent screening. Patients at high risk of death (male, on mechanical ventilation) should receive prompt treatment and intensive follow-up.