【Abstract】Objective To investigate the clinical significance of Vitamin K epoxide reductase complex 1 (VKORC1) and Cytochrome P450 2C9*3 (CYP2C9*3) gene polymorphismsdetection in guiding patients with acute pulmonary thromboembolism (PTE) to receive warfarin anticoagulant therapy. Methods Non-high-riskpatients with acute PTE who were treated with warfarin anticoagulant therapy in West China Hospital of Sichuan University were retrospectively collected. According to whether VKORC1 and CYP2C9*3 gene polymorphisms were detected and the initial dose and adjustment scheme of warfarin were formulated, they were divided into experimental group (gene detection guidedgroup, n=119) and control group (conventional treatment group, n=292). The primary endpoint was the interval time (d) from the beginning of warfarin use to achieving the first standard of international normalized ratio (INR) (2-3). The secondary endpoint was the maintenance dose of warfarin. Results AA wild type was the mainly genetic polymorphism of VKORC1 (n=89,74.8%), followed by GA heterozygous mutation (n=29,24.4%). Homozygous mutation GG was found only in 1 case (0.8%). There were 106 cases (89.1%) of CYP2C9*3 wild type (AA type) and 13 cases (10.9%) of heterozygous mutation (AC type). VKORC1 AA combined with CYP2C9 * 3 AA were detected in 81 cases (68.1%), followed by 24 cases (20.2%) of VKORC1 GA combined with CYP2C9*3 AAand 5 cases (4.20%) with VKORC1 and CYP2C9*3 mutation.The interval time (d) from the beginning of warfarin use to achieving the first standard INR in the experimental group was (7.96±4.02) d, and that in the control group was (7.68±3.58) d. There was no significant difference between the two groups (P=0.494). Moreover, the maintenance dose of warfarin in the experimental group was (5.30±0.99) mg, and that in the control group was (5.22±0.64) mg, with no significant difference (P=0.317). The proportion of death, massive hemorrhage and new thrombosis in the two groups were similar as well (P＞0.05). Conclusion The significance of VKORC1 and CYP2C9*3 gene polymorphisms detection in guiding acute PTE patients to receive warfarin anticoagulant therapy was limited.