Objective:To explore the relationship of CDH17 expression with clinico-pathological features and the correlation be-tween the single nucleotide polymorphisms (SNPs) of CDH17 gene and genetic susceptibility of gastric carcinoma (GC). Methods:A tissue microarray was performed to simulate the dynamic process of invasion and metastasis of GC. Immunohistochemical staining was performed to detect the expression of CDH17 protein, and PCR-based LDR was performed to detect the 2 SNP loci (rs2514813 and rs3214050) genotypes of CDH17 gene. Results: The expression of CDH17 protein in GC was more significantly up-regulated and greatly increased in the intestinal type than in the diffuse type. The expression of CDH17 protein in GC was positively correlated with the histological grading (P<0.01) and was not associated with the survival (P=0.209). With the progression of the cancer invasion, the expression of CDH17 protein in GC showed a downtrend from the gastric mucosa layer to the invasive front edge. The frequencies of the C and T alleles and the CC, CT, and TT genotypes at the CDH17 rs3214050 locus between the GC patients and the control groups were significantly different (P<0.01). However, no significant differences were observed at rs2514813 (P>0.05). The individuals with the T al-leles had longer survival time than those with the CC genotype (P<0.01). Conclusion:The up-regulation of CDH17 expression is in-volved in the maintenance of histological phenotype and progression of GC. Individuals with T alleles at the CDH17 rs3214050 locus have decreased risk of GC and had better prognosis (OR=0.762, 95%CI:0.619-0.937), thereby suggesting that screening for these alleles would help with the assessment of genetic susceptibility and prognosis of GC in the Fujian population.