Abstract: Objective To study the relationship between the expression of NKG2D ligands and oxidative stress，and analyze the effect of oxidative stress on the function of NK cells. Methods Tumor cells were cultured and exposed to hydrogen peroxide to make an oxidative stress model. Then we detected the expression of NKG2D ligands in cells by Real-time PCR and Flow Cytometry. The cytotoxicity of NK cells to tumor cells was detected and compared by CCK-8 kit before and after oxidative stress. Results The expression of NKG2D ligands could be induced by oxidative stress，however the NKG2D ligands induced was variable. The up-regulation of NKG2D ligands increased the cytotoxicity of NK cells efficiently, and this effect could be blocked by anti-NKG2D antibody. Conclusion The expression of NKG2D ligands could be selectively induced by oxidative stress on tumor cells, and the improvement of the cytotoxicity of NK cells may enhance the immune responses accordingly.