composite neoplasms, carcinoid and adenocarcinoma have been reported to occur in several parts of the body, including the stomach, ampulla of vater, large bowel, lung, and urinary bladder. here we report a case of a 74-year-old male with a composite carcinoid-adenocarcinoma of the ileum associated with a transitional cell carcinoma of the bladder. the microscopical examination of the composite tumor showed an admixture of typical carcinoid tumor and moderately a differentiated adenocarcinoma. immunohistochemically, the two components showed clear-cut differentiations. a review of the literature revealed that this is the first reported case of composite carcinoid-adenocarcinoma of the ileum associated with transitional cell carcinoma of the urinary bladder.