The genetic polymorphisms in E-cadherin gene (CDH1) may affect invasive/metastatic development of gastric cancer by altering gene transcriptional activity of epithelial cell. Our study aims to explore the associations among CDH1 gene polymorphisms, and predisposition of gastric cancer. We genotyped four potentially functional polymorphisms (rs13689, rs1801552, rs16260 and rs17690554) of the CDH1 gene in a case-control study of 387 incident gastric cancer cases and 392 healthy controls by polymerase chain reaction-ligation detection reaction methods (PCR-LDR) and measured the plasma CDH1 levels using enzyme immunoassay among the subjects. The median and inter-quartile range were adopted for representing the mean level of non-normally distributed data, and we found the level of plasma CDH1 in gastric cancer patients (median: 171.00 pg/ml; inter-quartile range: 257.10 pg/ml) were significantly higher than that of controls (median: 137.40 pg/ml; inter-quartile range: 83.90 pg/ml, P = 0.003). However, none of the four polymorphisms or their haplotypes achieved significant differences in their distributions between gastric cancer cases and controls, and interestingly, in the subgroup analysis of gastric cancer, we found that CA genotype of rs26160 and CG genotype of rs17690554 were associated with the risk of diffuse gastric cancer, compared with their wild genotypes (OR = 2.98, 95 % CI: 1.60-5.53; OR = 2.10, 95 % CI: 1.14-3.85, respectively, P < 0.05). In conclusion, our results indicated that plasma CDH1 levels may serve as a risk marker against gastric cancer and variant genotypes of rs26160 and rs17690554 may contribute to the etiology of diffuse gastric cancer in this study. Further studies are warranted to verify these findings.