Diseases affecting the biliary tract are very frequent occurrence in our part of the country. The commonest type of chronic biliary tract disease, which we frequently encounter in surgical department of Darbhanga Medical College and Hospital is chronic cholecystitis with or without cholelithiasis and investigation were done at Pathology Department of DMC, Laheriasarai, Bihar. Other less frequent disease affecting the biliary tract are carcinoma of the gall bladder, carcinoma of the bile duct, cholesterosis,, cholesterol polyposis and some congenital anomalies affecting the biliary tract. Cholecystectomy, a operative treatment for many of the chronic biliary tract disease is among the few major operation which is very frequently done in routine operation theatre of DMCH, Laheriasarai, Bihar. Duration of the biliary tract disease are very variable. Since the biliary system and parenchymal cell of the liver are interdependent, so it is likely that a disease of the biliary system, particularly of long duration may cause morphological or even functional abnormality in the liver.