We report a case of ileal perforation associated with Cytomegaloviral enteritis in a 62 years old man who was diagnosed as AIDS lately. The perforated lesian was located at distal ileum approximately 50 cm above ileo-cecal valve. The lesion was simply closed by surgery. There were numerous erythematous patches on the serosal surface of jejunoileum. His gastrofiberscopic examination revealed multiple shallow ulcers in distal esophagus and stomach. Mieroscopic findings of both surgical and endoscopic specimens showed characteristic cytonegalic cells with inclusion bodies. There were numerous cytomegalic endothelial cells found in the ileal specimen without direct evidence of vasculitis. The diagnosis was confirmed by colorimetric detection of cytomegalovirus DNA using in situ hybridization. (Korean J Gastrointest Endosc 18: 931- 936, 1998)