A case of ileal adenomyoma with goblet and Paneth cells is reported. A 75-year-old man died of ruptured hepatocellular carcinoma. As an incidental finding at autopsy, a 9 x 7 x 6 mm(3)-sized nodule was found in the ileal wall. Histologically, the lesion occupied the submucosa and muscularis propria, and consisted of glandular structures of various sizes and interlacing smooth muscle bundles surrounding the glandular elements. Goblet cells and Paneth cells were interspersed in the glandular element. Immunohistochemically, the glandular element was positive for cytokeratin (CK) 7 and negative for CK 20. This is the first reported case of adenomyoma of the gastrointestinal tract that contained Paneth cells. The result of the immunohistochemical staining favored the heterotopic pancreas theory concerning its pathogenesis. The appearance of goblet and Paneth cells might be the result of metaplasia.