Abstract: Objective To explore the association between single nucleotide polymorphisms(SNPs in Dopa decarboxylase(DDC) and dopamine receptor-1(DRD1) genes and childhood autism in Chinese Han population. Methods TaqMan Probes Real-Time PCR was used to determine genotype and allele frequency of SNPs of DDC gene (rs6592961)and DRD1 (rs251937)gene in 97 Chinese autism children and 100 healthy children.The Children Autism Rating Scale(CARS) was used to evaluate clinical phenotype feature.The allele and genotype between case group and control group were analyzed by Chi-square test. Results ①There was no statistically significant correlation to allele or genotype between control group and case group(P＞0.05).②There was no statistically significant correlation between allele or genotype of SNPs of DDC gene(rs6592961)and DRD1 gene(rs251937)and the degree of autism(P＞0.05). Conclusion The SNP of DDC gene(rs6592961)and DRD1 gene (rs251937)may not be related to childhood autism in Chinese Han population.