Cytomegalovirus(CMV) infection of the gastrointestinal tract has been reported most frequently in the setting of immunodeficiency. The whole gastrointestinal tract can be affected; however, the small bowel is rarely affected. We report a case of CMV enteritis with jejunal perforation in a 53-year-old woman with a history of chemoradiation therapy for endometrial cancer 8 years previously. At follow-up evaluation, lower abdominal pain, diarrhea and vomiting appeared. Abdominal computed tomography showed intra-abdominal free air in the subphrenic space and porta hepatis. The jejunal segment revealed serosal purulent exudates with a perforation. The resected jejunal segment showed a large geographic ulcerative mucosal lesion. The microscopic findings revealed a diffuse ulcerative mucosal change with a prominent granulation tissue formation and many large atypical vascular endothelial cells and stromal fibroblasts with intranuclear or intracytoplasmic inclusion bodies. These cells were positive for CMV antibody. The final diagnosis was CMV-associated jejunitis with a jejunal perforation. Cytomegalovirus (CMV) infection of the gastrointestinal tract has been reported most frequently in the setting of immunodeficiency. The whole gastrointestinal tract can be affected; however, the small bowel is rarely affected. We report a case of CMV enteritis with jejunal perforation in a 53 -year-old woman with a history of chemoradiation therapy for endometrial cancer for 8 years previously. At follow-up evaluation, lower abdominal pain, diarrhea and vomiting. Abdominal computed tomography showed intra-abdominal free air in the subphrenic space and porta hepatis. The resected jejunal segment showed a large geographic ulcerative mucosal lesion. The microscopic findings revealed a diffuse ulcerative mucosal change with a prominent granulation tissue formation and many large atypical vascular endothelial cells and stromal fibroblasts with intranuclear or intracytoplasmic inclusion bodies. These cells were pos itive for CMV antibody. The final diagnosis was CMV-associated jejunitis with a jejunal perforation.