Abstract: Objective To analyze thedistribution law of memory T cells and Treg cells in patients with gastric cancer and their relationship with clinicpathologic characteristics. Methods From January 2013 to June 2014, there were 140 patients with gastric cancer in our hospital served as gastric cancer group and 62 healthy volunteers as control group. 10 ml of peripheral blood was extracted and mononuclear cells were separated. The percentage of CD4⁺T_CM(CD4⁺CD45RO⁺CD62L⁺) and CD8⁺T_CM(CD8⁺CD45RO⁺CD62L⁺) and Treg (CD3⁺CD4⁺CD25⁺FOXP3⁺) in the peripheral blood wasdetected by flow cytometry, the immune memory characteristics of gastric cancer patients and normal subjects were compared, and the relationship of memory T cells and Treg cells with clinicpathologic characteristics of gastric cancer was analyzed. Results Compared with healthy volunteers, the mean percentage of CD4⁺T_CMand CD8⁺T_CMand Treg in gastric cancer patients increased significantly (CD4⁺T_CM: 43.32%±9.86% vs 36.97%±6.72%, P=0.022; CD8⁺T_CM: 16.79%±9.43% vs 11.41%±4.67%, P=0.028; Treg: 1.19%±0.24% vs 0.18%±0.09%, P=0.000), which was related to the lymph nodes involvement. Conclusion Patients with gastric cancer show immune suppression status with limited pre-exist anti-tumor immunity.