To evaluate the change of plasma level of retinol binding protein 4 (RBP4) in patients with coronary heart disease, and to explore the effect of hyperinsulinemia. This study was carried out at Xiangya Hospital of Central South University, China, from September 2009 to May 2010. Thirty patients with coronary artery disease (the CAD group) were confirmed by coronary angiography, 29 patients with CAD plus hyperinsulinemia (the CAD+HIns group), and 30 healthy subjects were enrolled as controls (the control group). The peripheral blood sample from the anticubital vein was collected aseptically in all the subjects to measure the RBP4 by enzyme linked immunosorbent-assay (ELISA). The height, weight, body mass index (BMI) the waist-to-hip ratio (WHR), the blood pressure, the fasting plasma glucose (FPG), the fasting insulin (Fins), the 2-hour postprandial inslulin (2hPIns), and the homeostasis model assessment-insulin resistance index (HOMA-IR) was measured. The lipids, high sensitivity C reactive protein (hsCRP), uric acid(UA), free fatty acids (FFA) were all examined. The level of plasma RBP4 in the CAD+HIns group was higher than that in the CAD group and the control group (both P<0.01), with no significant difference of plasma RBP4 between the CAD group and the control group (P>0.05). Correlation analysis showed that the plasma RBP4 level was significantly correlated with BMI, FPG, FIns, 2hPIns, HOMA-IR, TG, HDL-C, UA, and hsCRP (r=0.259, 0.331, 0.582, 0.452, 0.600, 0.236, -0.290, 0.243, 0.231, respectively; all P>0.05). Multiple regression analysis showed that BMI, 2hPIns, and HOMA-IR were the independent factors related to RBP4. The plasma level of RBP4 does not increase in the CAD group, but it is high in the CAD +HIns group. RBP4 level is related to BMI, lipids, UA, and other cardiovascular risk factors. BMI, 2hPIns, and HOMA-IR are the independent factors associated with RBP4.