Aim To investigate the effect and mechanism of retinoid X receptor(RXR)activation on macrophage apoptosis induced by oxidized low density lipoprotein(ox-LDL).Methods Ox-LDL-treated RAW264.7 murine macrophage cell line was induced apoptosis after 24 h.The effect of RXR special ligands 9-cisRA and SR11237 on the apoptosis induced by ox-LDL was studied.Cell viability was assayed by MTT.The apoptotic percentage of cells was measured by flow cytometry using propidium iodide(PI) staining and DAPI staining.Cellular reactive oxygen species production was detected by CM-H2DCFDA fluorescent probe.Results The cell viability of ox-LDL-treated RAW264.7 cells were decreased by about 60% and cell apoptotic percentage was increased by about 75% compared with control respectively.9-cisRA of 10-8 mol/L and 10-7 mol/L,SR11237 of 10-6 mol/L significantly inhibited this decreased cell viability and increased cell apoptotic percentage(P<0.05),which showed dose-dependent manner.Ox-LDL-treated RAW264.7 acquired significantly increasing cellular reactive oxygen species by more than 17 folds.And it was significantly reduced by 10-7 mol/L 9-cisRA to 52% and by 10-6 mol/L SR11237 to 28% compared with control.Conclusion RXR activation can inhibit macrophage apoptosis induced by ox-LDL,which may be related to reducing oxidative stress injury.