Objective To discuss the value of hypotonic-MRCP combined with LAVA dynamic contrast-enhanced scan in diagnosis of duodenal tumor.Methods Five patients with duodenal adenocarcinomas confirmed by pathology were involved in this study.All cases underwent plain MRI and hypotonic-MRCP and LAVA dynamic contrast-enhanced scans.Results 4 of 5 cases were correctly diagnosed with MR imaging.Imaging signs included:the cavum of descending duodenum appeared as asymmetrical stenosis,masses with soft tissue signal intensity connecting the intestinal wall with wide base,the intestinal wall stiff,the intestinal mucosa destruction.The lesions would be slightly-moderately enhanced at LAVA dynamic enhancement scanning.Conclusion Hypotonic-MRCP combined with LAVA dynamic contrast-enhanced scan can display the direct and indirect sign of duodenal tumors,which was effective in identifying the circumscription of the tumor and its extension.