Objective: To study the change of chemokine receptor CXCR2 in monocytes in postmenopausal women with coronary artery disease (CAD) after estrogen replacement therapy. Methods: Randomized placebo controlled trial was conducted in 22 post menopausal women with CAD and 20 normal menopausal women by giving 0.625 mg premarin daily or vitamin C treatment for 3 months. Serum estradiol (E 2) and chemokine receptor CXCR2 in peripheral blood monocytes were measured at 0 and 3 months of treatment. Results:(1) E 2 and CXCR2 levels in the CAD group was lower than that in the normal group ( P