Objective：To study the effect of Staphylococcus aureus α-hemolysin mutant H35A on the wild type α-hemolysin（Hla） toxicity in human periphery blood mononuclear cells（hPBMC） and THP-1 macrophages. Methods： hPBMC and THP-1 macrophages were stimulated with both H35A and Hla. The transcriptions of interleukin-1β （IL-1β），interleukin-6 （IL-6），tumor necrosis factor-α（TNF-α） mRNA in hPBMC and THP-1 macrophages were assayed by real-time Q-PCR. The survival percentage of THP-1 macrophages treated with Hla and H35A was calculated with Trypan blue staining. Results： The transcriptions of IL-1，IL-6 and TNF-α mRNA in hPBMC and THP-1 macrophages treated with H35A mutant were significantly decreased upon stimulation with Hla. The survival percentage of THP-1 macrophages treated with Hla and H35A was significantly increased. Conclusion： H35A mutant can inhibit the toxic effect of Hla on human monocytes and macrophages，and it is expected to be a therapeutic drug used in the early stage of Staphylococcus aureus infection.