Metaplasia of bile duct epithelium was studied clinicopathologically in 36 autopsy cases (Group-A), 18 surgical cases of obstructive jaundice without bile duct carcinoma (Group-B) and 56 surgical cases of bile duct carcinoma (Group-C). The results were as follows: In Group-A there were 24 cases with metaplastic pyrolic glands, and no metaplastic goblet cells. In group-B, there were 16 cases with metaplastic pyrolic glands, 2 cases with metaplastic goblet cells and 1 case with enterochromaffin cells. The mucosa of non-tumorous region of Group-C had metaplastic pyrolic glands in 46 cases, metaplastic goblet cells in 14 cases, enterochromaffin cells in 2 cases and intestinal absorbtive epithelia in 5 cases. In the tumorous region, however, tumor cells with goblet vesicles (malignant goblet cells) were seen in 31 cases, malignant intestinal absorptive villi were in 18 cases, malignant enterochromaffin cells were in 8 cases. Thirty one cases with malignant goblet cells were classified as intestinal type of the bile duct carcinoma (I-type). And 25 cases without malignant goblet cells were classified as non-intestinal type of the bile duct carcinoma (non-I-type). Conclusively, these clinicopathological findings suggest that I-type and non-I-type in the carcinoma of the bile duct are identifiable and I-type in the carcinoma of the bile duct are identifiable and I-type may arise from the lesion with intestinal metaplasia of the benign epithelia of the duct.