Imaging and clinical manifestations of viral pneumonia are protean and not reliably predictive of its origin. All patients with neutropenic fever and normal findings at chest radiography should undergo thin-section computed tomography to determine whether parenchyma abnormalities are present. Although the radiologic manifestations of viral pneumonia are nonspecific and difficult to differentiate from those of other infections, it is important to consider viral infection when confronted with a rapidly progressive pneumonia in patients with risk factors for infection. Although definitive diagnosis cannot be made on the basis of imaging features alone, the use of a combination of clinical and radiographic findings can substantially improve the accuracy of diagnosis in this disease.