Objective To investigate the distinct expression pattern of CD11c in gastric cancer tissues from patients of different tumor stages.Methods Immunohistochemistry was used to detect the expression of CD11c in tissues from 144 gastric cancer patients,10 gastritis patients,and 10 gastric polyps patients; Flow cytometry was used to analyze the expression of CD11 c on the membrane of lymphocyte from gastric cancer tissues ; Laser confocal was used to confirmed the position of CD11c.Results The immunohistochemistry results showed that the expression level of CD11c in gastric cancer tissues was significantly higher than that in gastritis and gastric polyps tissues.The expression level of CD11 c in patients with early gastric cancer was higher than patients with advanced [(12.2 ± 6.5)/HPF vs 9.0 ± 6.1)/HPF],and the difference was statistically significant (t =2.77,P < 0.01).Flow cytometry showed the expression of CD1 1c with higher tumor stage was significantly reduced than early tumor stage.The confocal laser also confirmed the co-infiltration of CD11c+ dendritic cell (DCs) and CD8 + cytotoxic T lymphocyte (CTL)cells in tumor sites.Conclusion The expression pattern of CD11 in different stages of gastric cancer patients is distinct. Key words: Gastric cancer; CD11c; Adhesion molecule; Immunohistochemistry; Confocal laser