CD86, one of the key costimulatory molecules, is not only involved in the initiation of T-cell immunity but also plays important roles in the development of cardiovascular diseases. The purpose of this study was to investigate the association between the CD86 polymorphism and the risk of coronary artery disease (CAD) in a Chinese population. We analyzed single-nucleotide polymorphism of CD86 +1057G/A (rs1129055) in 164 patients with CAD and 299 healthy controls by performing polymerase chain reaction-restriction fragment length polymorphism and DNA sequencing assay. No significant association was observed in the genotype and allele frequencies of +1057G/A polymorphism between cases and controls, indicating that CD86 +1057G/A polymorphism may not be associated with CAD in the Chinese population.