Objective To evaluate the diagnostic efficiency and accuracy of endoscopic ultrasonography (EUS) on vascular involvement of pancreatic cancer. Methods Patients, suspected pancreatic cancer with vascular involvement by CT scan in Huashan Hospital, Fudan University from January 2014 to March 2019, were enrolled prospectively in the study. EUS was performed to evaluate the vascular involvement compared with surgical pathological results. Results A total of 132 patients with pancreatic cancer were enrolled in the study, and they all underwent EUS observation and radical resection with vessels resection. There were 103 cases of cancer in pancreatic head, 19 cancers in pancreatic neck and 10 cancers in distal pancreas. The diagnostic sensitivity, specificity and accuracy of EUS was 97.4% (113/116), 81.2% (13/16), and 95.5% (126/132), respectively for pancreatic cancers with vein involvement; while was 33.3% (2/6), 90.0% (81/90), and 86.5% (83/96), respectively, for pancreatic cancers with superior mesentery artery involvement. Conclusion EUS may play a key role in diagnosis of vascular involvement of pancreatic cancer, and be helpful for the surgical decision marking.