Abstract： Objective To investigate the role of prostate stem cell antigen (PSCA) in perineural invasion of pancreatic carcinoma. Methods Eighty patients with pancreatic carcinoma were analyzed with histopathologic and immunohistochemical (SABC) methods. The overall PSCA expression rate, perineural, lymphatic and vascular vessel invasion were recorded. Results Perineurel invasion was positively correlated with lymphatic and vascular vessel invasion(P <0.01). A positive correlation was found between tumor PSCA expressioa (53 eases) and peri-neurel invasion (66 cases). A definite correlation was also found between cancer differentiation and PSCA expres-sion. Conclusion PSCA is one of the most important molecules and may play a role as a "navigating" and "doc-king" molecule in progress of perineural invasion.