Abstract The histopathologic features of 34 resected carcinomas of the upper bile duct were reviewed. Patients with papillary adenocarcinoma showed a 3-year survival rate of 75 percent, which was better than those with poorly differentiated adenocarcinoma with no 2-year survivors. Infiltration to the serosa of the bile duct, lymph node metastasis, and vascular invasion were important prognostic factors, since the survival was better for the patients without than those with these factors. Among patients with papillary adenocarcinoma, none had hepatic infiltration and lymph node metastasis and most had no infiltration to the serosa. Patients with poorly differentiated adenocarcinoma, in contrast, had extensive association of those prognostic factors. Seventy-five percent of the patients with papillary adenocarcinoma and only 22 percent of patients with poorly differentiated adenocarcinoma were considered to have curative resection. These findings suggest that the histologic type strongly influenced the prognosis of the patients with carcinoma of the upper bile duct and can be used for the determination of the extent of this tumor.