Abstract: Objective To investigate effect of erythrocyte immunization on induction of gastric cancer cell apoptosis and the synergistic action of lymphocytes. Methods Gastric cancer cells with normal erythrocyte, erythrocyte-lymphocyte were cultured in vitro. ATER (associated tumor cell erythrocyte rosette), FCM ( flow cytometry) and RIA (radioimmunoassay) were used to determine percentage of the erythrocyte rosette of erythrocyte group and mixed group, the rate of apoptosis,expression of Fas, Bcl-2 and the level of cAMP, PKC(protein kinase C) in gastric cancer cells. Results The percentage of ATER of erythrocyte group is (28.41 + 5.01 ) %. The expression of Fas, the apoptosis rate increased significantly, the level of cAMP increased significantly, the level of PKC decreased significantly ( P ＜ 0.01 ). In mixed group, the percentage of mixed rosette is (32.28 ±5.37) %, significantly higher than erythrocyte group, the apoptosis rate and the expression of Fasincreased more, the level of cAMP increased more, the Bcl-2 and PKC decreased more ( P ＜0.01).Conclusion Erythrocytes can adhere BGC- 823 cells cultured in vitro. After immunization, especially immune adhesion, erythrocyte may enhance the expression of Fas, increase the level of cAMP of erythrocyte, decreased the level of PKC, effect the apoptosis of gastric cancer cells. The lymphocyte may has synergistic effect.