Histochemical features of the intrahepatic bile ducts and peribiliary glands were examined with five biotinylated lectins in 12 normal human livers and 12 livers with hepatolithiasis. There was a marked proliferation of peribiliary glands, especially mucous cells, in the stone-containing bile ducts. Based on the carbohydrate binding specificity for each lectin, it was found in both the normal and hepatolithiasis livers, that N-acetylglucosamine, N-acetylgalactosamine, D-galactose and L-fucose were abundant in the mucous acinar cells of the intrahepatic peribiliary glands, and mannose (or glucose) was present exclusively in the serous acinar cells and surface lining epithelium. Considerable case to case and cell to cell variations, however, were noted in the expression of lectin binding activity. It has been shown that major monosaccharide components of biliary glycoproteins are N-acetylglucosamine, galactose and fucose. All of these carbohydrates were detected in the peribiliary glands, especially mucous acinar cells, in this study. Therefore, the peribiliary mucous cells are mainly responsible for the secretion of the glycoproteins with these carbohydrates into the hepatic bile, and may play a role in the calculi formation in the intrahepatic biliary tree.