bstract: Objective To investigate the correlation between the polymorphism of CYP2C19, ALDH2 and MTHFR with coronary heart disease. Methods The genotypes of the CYP2C19, ALDH2 and MTHFR were detected by DNA microarray and PCR-chip hybridization technology in 199 patients with coronary heart disease and 160 controls. Results The frequencies of CYP2C19 *2/*2, ALDH2 AA and MTHFR TT were 8.9%, 12.3% and 34.9% in coronary heart disease patients, 3.6%, 1.8% and 4.1% in controls, which showed significant differences between two groups (P<0.05). The ALDH2 and MTHFR polymorphism were the main risk factors for coronary heart disease. The OR value of genotype ALDH2 GA and AA was 2.09, MTHFR CT and TT was 2.11. Conclusion The genetic polymorphism of ALDH2 and MTHFR may increase the risk for coronary heart disease