Objective: To evaluate the manifestation of pancreatic head carcinoma and chronic pancreatitis of pancreatic head on magnetic resonance (MR) imaging and to determine whether MR imaging can distinguish the two diseases. Methods: A retrospective review of MR findings was performed for 24 patients with pancreatic head carcinoma and 3 patients with chronic pancreatitis of pancreatic head. SE T1WI and FSE T2WI sequences with and without fat suppression were performed on all 27 cases. Enhanced SE T1WI with fat suppression was performed on 8 patients with carcinomas and 3 patients with pancreatitis, respectively. When dilatation of the pancreatic and/or biliary ducts was noted on T2WI sequence, MRCP were performed on 23 patients with carcinoma and 1 patient with pancreatitis, respectively. Results: Cases of carcinoma presented hypointensity (n=8) or mild hypointensity (n=16) on conventional SE T1WI, hyperintensity (n=8), mild hyperintensity (n=5), isointensity (n=10) or hypointensity (n=1) on conventional FSE T2WI, hyperintensity (n=11), isointensity (n=11) or mild hypointensity (n=2) on FSE T2WI with fat suppression, and hypointensity (n=24) on fat-suppressed SE T1WI. MRCP demonstrated typical “double duct sign” and abrupt interruption at distal segment of dilated common bile duct. All 8 patients with carcinoma showed little enhancement. All 3 patients with chronic pancreatitis showed mild hypointensity or iosintensity on conventional SE T1WI and hyperintensity on conventional FSE T2WI sequences, respectively. Two patients showed isointensity and mild hyperintensity on fat-suppressed SE T1WI and FSE T2WI sequences, respectively. The remaining patient showed hypointensity and heterogeneous intensity on fat-suppressed SE T1WI and FSE T2WI sequences respectively and a mild dilated common biliary duct with irregularly dilated proximal pancreatic duct on MRCP. All 3 patients with chronic pancreatitis showed various enhancements. Conclusion: Both pancreatic head carcinoma and chronic pancreatitis show various signals on various sequences and abnormal pancreatic enhancement pattern and most cases of pancreatic head carcinoma and some cases of chronic pancreatitis show abnormal MRCP appearances. With the combined use of multiple sequences, especially precontrast and postcontrast SE T1WI FS and MRCP, pancreatic head carcinoma and chronic pancreatitis of pancreatic head may be distinguished from each other.