ABSTRACT. We conducted a case-control study to investigate the association between the interleukin-10 (IL-10) C819T polymorphism and susceptibility to gastric cancer in a Chinese population. A total of 157 patients with gastric cancer and 249 controls were consecutively enrolled from the Guizhou Provincial People's Hospital between October 2012 and February 2015. The polymerase chain reactionrestriction fragment length polymorphism technique was used to genotype for IL-10 C819T. As determined by c 2 -test, there was a significant difference in genotype distributions of IL-10 C819T between gastric cancer patients and controls (c 2 = 7.09; P = 0.03). Based on unconditional logistic regression analysis, the TT genotype of IL-10 C819T was significantly associated with increased risk of gastric cancer when compared with that of the CC genotype [odds ratio (OR) = 2.24; 95% confidence interval (CI) = 1.17-4.26; P = 0.008]. In a dominant model, we found that the CT + TT genotype of IL-10 C819T was associated with susceptibility to gastric cancer compared to that of the CC genotype (OR = 1.63; 95%CI = 1.02-2.64). In a recessive model, the TT genotype of IL-10 C819T was correlated with a higher risk of gastric cancer when compared with that of the CC + CT genotype (OR = 1.75; 95%CI = 1.01-3.02). In conclusion, our study suggests that the IL-10 C819T polymorphism is associated with an increased risk of gastric cancer in co-dominant, dominant, and recessive models.