Aim To study the association between the polymorphism in the promoter region in human paraoxonase(PON1) gene and coronary heart disease(CHD)in Chinese population.Methods The genotype and allele frequency of paraoxonase1 gene polymorphism were assayed by polymerase chain reaction(PCR)-restriction fragment length polymorphism(RFLP).Results The frequencies of PON1-162A/G genotype and allele in control were 0.047,0.203,0.750 and 0.148,0.852,respectively.There was no significant difference in genotype and allel frequency between control and CHD group.The frequencies of PON1-909C/G genotype and allele in control were 0.258,0.523,0.219 and 0.520,0.480,respectively. There was no significant difference in genotype and allel frequency between control and CHD group.Increasing number of hazardous genotype of PON1 was not associated with CHD.Conclusions These results suggested that PON1-162A/G、PON1-909C/G gene polymorphism were not associated with CHD in Chinese population.There was no cooperative effect among these hazardous genotype with CHD.