In 48-year-old female, patient suffering from debilitating disease, who was treated with antibiotics, steroids and transfusion for the fever of unknown origin for 15 months, cytomegalovirus (CMV) infected cells were observed in the gastric biopsy specimens cytologically and histologically three months befor death.In the autopsy materials, CMV infected cells were also found in the gastric mucosa and renal tubules.Cytologic appearances of CMV infected cells vary in intra-cellular structures. Some infected cells have the characteristic intranuclear inclusion bodies with surrounding clear halo, the so-called “owl's eye” appearance.Irregular or dim intranuclear halo, and/or coarse granules in their abundant cytoplasm were observed in the other infected cells. All infected cells, however, were greatly enlarged and were spherical, having the homogeneous inclusion bodies in the nuclei. The diagnosis of disseminated CMV infection disease could be made cytologically and histologically.