Objective To study the effects of 17estradiol on chemokine receptor CXCR2 expression in monocytes incubated with oxidized low density lipoproteins (oxLDL). Methods Human monocytic U937 cells were used as a model of monocytes. Expressions of CXC chemokine receptor CXCR2 mRNA and protein were measured by RT-PCR and FACS, respectively. Results The oxLDL(50 ?g/ml) significantly upregulated CXCR2 expression in U937 cells. 17estradiol (50 nmol/L) reduced expressions of CXCR2 mRNA and protein in U937 cells incubated with oxLDL (50 ?g/ml) , and the decrease of the CXCR2 protein was dependent on the concentration of 17estradiol (5-500 nmol/L). Conclusions 17estradiol can obviously reverse oxLDL-induced CXC chemokine receptor CXCR2 expression in U937 cells.