【Abstract】ObjectiveTo evaluate the clinical value of magnetic resonance cholangiopancreatography (MRCP) in diagnosis of extrahepatic bile duct obstruction. MethodsMRCP images of 42 patients presented clinically with obstructive jaundice were retrospectively reviewed to assess the lumen morphological abnormalities of benign versus malignant bile duct obstructions, with clinicalpathological correlation. ResultsThe bile duct of the 30 cases of benign biliary obstruction presented regular and symmetric dilation, gradual tapering,regular thickening and had a “beaklike” tip. The accuracy of MRCP for evaluating the site and the etiology of the benign biliary obstruction were 100%(30/30) and 97%(29/30) respectively. The bile duct of the 12 cases of malignant biliary obstruction presented irregular and asymmetric dilation,abrupt narrowing or iterruption,irregular thickening and had “dualduct sign”. The accuracy of MRCP for evaluating the site and the etiology of the malignant biliary obstruction were 100%(12/12) and 92%(11/12) respectively. ConclusionMRCP is the noninvasive technique of choice with excellent accuracy for the evaluation of obstructive biliary pathology.