Diabetes is known to be a high-risk factor for coronary artery disease (CAD), and lipid abnormalities have been found to possibly contribute to CAD in diabetic patients. Cholesteryl ester transfer protein (CETP) gene TaqIB polymorphism is associated with lipid profile variability, and this polymorphism may be a risk factor for CAD in diabetic patients. To clarify the relationship between CETP TaqIB gene polymorphism and CAD, we enrolled in our study 365 Taiwanese with type 2 diabetes mellitus (101 with CAD and 264 without CAD). The genotype of the subjects for TaqIB polymorphism of CETP in intron 1 was analyzed by using polymerase chain reaction-restriction fragment length polymorphism. The CETP B1B1 genotype (18.8% vs 8.5%, P = .002) and B1 allele (42.1% vs 29.7%, P = .002) were significantly more frequent in diabetic patients with CAD than those without CAD. Logistic regression analysis revealed that the CETP B1B1 genotype was associated with CAD in patients with type 2 diabetes mellitus (odds ratio, 3.18; 95% confidence interval, 1.54-6.54; P = .002). Interestingly, in diabetic patients, serum creatinine levels higher than 1.4 mg/dL were also associated with increased risk for CAD (odds ratio, 2.09; 95% confidence interval, 1.12-3.91; P = .02). Our results suggest that the CETP B1B1 genotype is a strong genetic predictor of CAD in Taiwanese with type 2 diabetes mellitus.