Purpose: To evaluate the diagnostic role of a three-dimensional MR cholangiopancreatography (MRCP) over endoscopic retrograde cholangio-pancreatography (ERCP) in various extrah-epatic biliary disease. Materials and Methods: MRCP and ERCP were performed in 45 consecutive patients with suspected extrahepatic biliary diseases. MRCP was obtained using a reverse fast imaging with a steady-state free precession (reverse FISP: PSIF) sequence, and then images were reconstructed by standard MIP algorithm. The predictability of biliary dilatation and level of obstruction of MRCP was evaluated using ERCP as a gold standard. The accuracy distinguishing malignant from benign lesions, and overall diagnostic accuracy were compared between MRCP and ERCP. Results: The sensitivity, specificity and accuracy of MRCP in predicting biliary dilatation were 94.6%, 75.0% and 91.1%, respectively. The level of obstruction was accurate in 87.0% with MRCP. The sensitivity, specificity and accuracy of MRCP and ERCP in distinguishing malignant from benign lesions were 76.2%, 87.5% and 82.2% and 71.4%, 83.3% and 77.8%, respectively. The overall diagnostic accuracy was 60.0% with MRCP and 55.6% with ERCP. Conclusion: 3D MRCP shows a good diagnostic value compared to that of ERCP, and can replace a ERCP.