| Objective: To conduct a molecular epidemiological survey of Han women in Weifang and study the genetic polymorphisms of the key enzymes folate metabolism, MTHFR and MTRR. Methods: A total of 670 healthy women of Han nationality during pregnancy were taken as research objects. Exfoliated cells of oral mucosa were collected, genomic DNA was extracted, and MTHFR C677T, A1298C, and MTRR A66G gene polymorphisms were detected by fluorescent quantitative PCR for statistical analysis. Results: 1) The genetic polymorphism distribution of the subjects was in line with genetic balance. 2) The genotype frequencies of MTHFR 677CC, CT, and TT of Han women were 13.73%,47.91%,38.36%, and the C and T allele frequencies were 37.7% and 62.3%, respectively. The genotypes frequencies of MTHFR 1298AA, AC, and CC were 75.52%,23.28%,1.19%, respectively. The frequencies of the A and C alleles were 87.2% and 12.8%. The genotype frequencies of MTRR 66AA, AG, and GG were 54.63%,40.44%,4.93%. The G allele frequencies were 74.9% and 25.1%, respectively. 3) There are 7 combinations of two-point linkage between MTHFR C677T and A1298C for Han women. The highest frequency is TT/AA (38.21%). There is no CT/CC and TT/CC combination. There is a complete linkage disequilibrium between the two points (D'=0.987，r2=0.237). Conclusion: The population genetics of MTHFR and MTRR gene polymorphisms in Han women of Weifang City were obtained.