Abstract: OBJECTIVE To explore the influence of VKORC1-3673G>A, CYP2C9^*3, CYP4F2 rs2108622, and CYP2C19^*2 genetic polymorphism on maintenance warfarin dose in a Han-Chinese population with atrial fibrillation. METHODS Genetic polymorphisms were detected in 107 patients with atrial fibrillation receiving warfarin by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Independent-samples t-test was used to investigate the association between VKORC1-3673G>A, CYP2C9^*3, CYP4F2 rs2108622, and CYP2C19^*2 genetic polymorphisms and maintenance warfarin dose. Multiple linear regression analysis was used to investigate the contribution of genetic polymorphisms to maintenance warfarin dose. RESULTS VKORC1-3673G>A, CYP2C9^*3, CYP4F2 rs2108622 genotypes and clinical characteristics (age, body weight) could account for 45.2% of the variance in the warfarin maintenance dose in patients with atrial fibrillation. No relationship was found between the maintenance warfarin dose and CYP2C19^*2 genotype. CONCLUSION VKORC1-3673G>A, CYP2C9^*3 and CYP4F2 rs2108622 genetic polymorphism are significantly affect the maintenance warfarin dose in Han-Chinese patients with atrial fibrillation.