ObjectiveTo systematically review the expression of E-cadherin protein and the risk of pancreatic cancer. MethodsWe searched PubMed, EMbase, The Cochrane Library, CNKI, VIP, CBM and WanFang Data from inception to October 2016 to collect case-control studies about the correlation between E-cadherin protein expression and the risk of pancreatic cancer. Two reviewers independently screened the literature, extracted data and assessed the risk of bias of included studies. Then meta-analysis was performed using RevMan 5.2 software and Stata 12.0 software. ResultsSeventeen studies (986 cases in pancreatic cancer group and 433 cases in normal pancreatic tissue group) were finally included. The results of meta-analysis showed that: the expression of E-cadherin protein in the pancreatic cancer group was lower than normal tissue group (OR=0.04, 95%CI 0.01 to 0.23, P=0.000 2), poor differentiation group was lower than high or middle differentiation group (OR=0.44, 95%CI 0.26 to 0.76, P=0.003), lymph node metastasis group was lower than without lymph node metastasis group (OR=0.50, 95% CI 0.31 to 0.81, P=0.005), and the difference was statistically significant. However, there was no significant difference between the clinical stageⅠ-Ⅱ group and Ⅲ-Ⅳ group (OR=0.63, 95%CI 0.25 to 1.59, P=0.33), pancreatic head cancer group and pancreatic body and tail cancer group (OR=1.22, 95%CI 0.72 to 2.07, P=0.46), pancreatic cancer with nerve invasion group and without nerve invasion group (OR=1.45, 95%CI 0.81 to 2.62, P=0.21), pancreatic cancer with vascular invasion group and without vascular invasion group (OR=0.55, 95%CI 0.13 to 2.22, P=0.40). ConclusionLower expression of E-cadherin protein is significantly associated with the risk of pancreatic cancer. Due to the limited quality and quanity of includied studies, the above conclusion should be approved by more studies.